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Jianye Hao

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178 papers
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178

AAMAS Conference 2026 Conference Paper

Advancing Multi-Agent RAG Systems with Minimalist Reinforcement Learning

  • Yihong Wu
  • Liheng Ma
  • Muzhi Li
  • Jiaming Zhou
  • Lei Ding
  • Jianye Hao
  • Ho-fung Leung
  • Irwin King

Large Language Models (LLMs) equipped with modern Retrieval- Augmented Generation (RAG) systems often employ multi-turn interaction pipelines to interface with search engines for complex reasoning tasks. However, such multi-turn interactions inevitably produce long intermediate contexts, as context length grows exponentially with exploration depth. This leads to a well-known limitation of LLMs: their difficulty in effectively leveraging informationfromlongcontexts. ThisproblemisfurtheramplifiedinRAG systemsthatdependonin-contextlearning, wherefew-shotdemonstrations must also be included in the prompt, compounding the context-length bottleneck. To address these challenges, we propose Mujica-MyGo, a unified framework for efficient multi-turn reasoning in RAG. Inspired by the divide-and-conquer principle, we introduce Mujica (Multi-hop Joint Intelligence for Complex Question Answering), a multi-agent RAG workflow that decomposes multiturn interactions into cooperative sub-interactions, thereby mitigating long-context issues. To eliminate the dependency on in-context learning, we further develop MyGO (Minimalist Policy Gradient Optimization), a lightweight and efficient reinforcement learning algorithm that enables effective post-training of LLMs within complex RAG pipelines. We provide theoretical guarantees for MyGO’s convergence to the optimal policy. Empirical evaluations across diverse question-answering benchmarks—covering both text corpora and knowledge graphs—show that Mujica-MyGO achieves †qually contributed. This work is licensed under a Creative Commons Attribution International 4. 0 License. Proc. of the 25th International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2026), C. Amato, L. Dennis, V. Mascardi, J. Thangarajah (eds.), May 25 – 29, 2026, Paphos, Cyprus. © 2026 International Foundation for Autonomous Agents and Multiagent Systems (www. ifaamas. org). https: //doi. org/10. 65109/QCQC1144 superior performance. Proofs, implementation details, and prompt templates are available in the extended version 1.

AAAI Conference 2026 Conference Paper

AgentSwift: Efficient LLM Agent Design via Value-Guided Hierarchical Search

  • Yu Li
  • Lehui Li
  • Zhihao Wu
  • Qingmin Liao
  • Jianye Hao
  • Kun Shao
  • Fengli Xu

Large language model (LLM) agents have demonstrated strong capabilities across diverse domains, yet automated agent design remains a significant challenge. Current automated agent design approaches are often constrained by limited search spaces that primarily optimize workflows but fail to integrate crucial human-designed components like memory, planning, and tool use. Furthermore, these methods are hampered by high evaluation costs, as evaluating even a single new agent on a benchmark can require tens of dollars. The difficulty of this exploration is further exacerbated by inefficient search strategies that struggle to navigate the large design space effectively, making the discovery of novel agents a slow and resource-intensive process. To address these challenges, we propose AgentSwift, a novel framework for automated agent design. We formalize a hierarchical search space that jointly models agentic workflow and composable functional components. This structure moves beyond optimizing workflows alone by co-optimizing functional components, which enables the discovery of more complex and effective agent architectures. To make exploration within this expansive space feasible, we mitigate high evaluation costs by training a value model on a high-quality dataset, generated via a novel strategy combining combinatorial coverage and balanced Bayesian sampling for low-cost evaluation. Guiding the entire process is a hierarchical Monte Carlo Tree Search (MCTS) strategy, which is informed by uncertainty to efficiently navigate the search space. Evaluated across a comprehensive set of seven benchmarks spanning embodied, math, web, tool, and game domains, AgentSwift discovers agents that achieve an average performance gain of 8.34\% over both existing automated agent search methods and manually designed agents. Moreover, our framework exhibits steeper and more stable search trajectories. By enabling the efficient, automated composition of workflow with functional components, AgentSwift provides a scalable methodology to explore complex agent designs. Our framework serves as a launchpad for researchers to rapidly prototype and discover powerful agent architectures without the impediment of prohibitive evaluation costs.

TMLR Journal 2026 Journal Article

Extracting and Following Paths for Robust Relational Reasoning with Large Language Models

  • Ge Zhang
  • Mohammad Ali Alomrani
  • Hongjian Gu
  • Jiaming Zhou
  • Yaochen Hu
  • Bin Wang
  • Qun Liu
  • Mark Coates

Large language models (LLMs) possess vast semantic knowledge but often struggle with complex reasoning tasks, particularly in relational reasoning problems such as kinship or spatial reasoning. In this paper, we present Path-of-Thoughts (PoT), a novel framework for solving relation reasoning that decomposes the task into three key stages: graph extraction, path identification, and reasoning. Unlike previous approaches, PoT efficiently extracts a reasoning graph that identifies crucial entities, relations, and attributes within the context. Subsequently, PoT identifies query-relevant reasoning paths within the graph, facilitating downstream reasoning of potential answers. Experimental evaluations across four datasets of relational reasoning demonstrate that PoT surpasses state-of-the-art baselines by a significant margin (up to 21.3%) without requiring fine-tuning or extensive LLM calls. Furthermore, unlike prior neuro-symbolic methods, PoT exhibits improved resilience against LLM extraction errors and input ambiguity by leveraging the compositional nature of graphs.

AAMAS Conference 2026 Conference Paper

Towards A Unified Policy Abstraction Theory and Representation Learning Approach in Markov Decision Processes

  • Min Zhang
  • Hongyao Tang
  • Jianye Hao
  • Yan Zheng

In intelligent decision-making systems, how policy is represented and optimized is a fundamental problem. The root challenge stems from the large scale and the high complexity of policy space. Towards a desirable surrogate policy space, recent policy representations in a low-dimensional latent space has revealed its potential in improving both evaluation and optimization of policy. The key question to answer in this line of research is by what criterion the policy space should be abstracted for favorable compression and generalization. However, both the theory of policy abstraction and the method of policy representation learning are under-studied. In this work, we first make efforts to fill the vacancy. First, we propose a unified policy abstraction theory, containing three types of policy abstraction and explaining their partial ordering relationship. Then, we generalize policy abstractions to three policy metrics that quantify the distance between policies. Further, we propose a policy representation learning approach and policy optimization algorithm based on deep metric learning. Our study highlights the importance of policy abstraction theory and representation method, demonstratingtheireffectivenessincompressingpolicyspace, characterizing policy differences, and conveying policy generalization.

ICLR Conference 2025 Conference Paper

3D-AffordanceLLM: Harnessing Large Language Models for Open-Vocabulary Affordance Detection in 3D Worlds

  • Hengshuo Chu
  • Xiang Deng 0002
  • Qi Lv 0001
  • Xiaoyang Chen
  • Yinchuan Li
  • Jianye Hao
  • Liqiang Nie

3D Affordance detection is a challenging problem with broad applications on various robotic tasks. Existing methods typically formulate the detection paradigm as a label-based semantic segmentation task. This paradigm relies on predefined labels and lacks the ability to comprehend complex natural language, resulting in limited generalization in open-world scene. To address these limitations, we reformulate the traditional affordance detection paradigm into \textit{Instruction Reasoning Affordance Segmentation} (IRAS) task. This task is designed to output a affordance mask region given a query reasoning text, which avoids fixed categories of input labels. We accordingly propose the \textit{3D-AffordanceLLM} (3D-ADLLM), a framework designed for reasoning affordance detection in 3D open-scene. Specifically, 3D-ADLLM introduces large language models (LLMs) to 3D affordance perception with a custom-designed decoder for generating affordance masks, thus achieving open-world reasoning affordance detection. In addition, given the scarcity of 3D affordance datasets for training large models, we seek to extract knowledge from general segmentation data and transfer it to affordance detection. Thus, we propose a multi-stage training strategy that begins with a novel pre-training task, i.e., \textit{Referring Object Part Segmentation}~(ROPS). This stage is designed to equip the model with general recognition and segmentation capabilities at the object-part level. Then followed by fine-tuning with the IRAS task, 3D-ADLLM obtains the reasoning ability for affordance detection. In summary, 3D-ADLLM leverages the rich world knowledge and human-object interaction reasoning ability of LLMs, achieving approximately an 8\% improvement in mIoU on open-vocabulary affordance detection tasks.

ICLR Conference 2025 Conference Paper

A Graph Enhanced Symbolic Discovery Framework For Efficient Logic Optimization

  • Yinqi Bai
  • Jie Wang 0005
  • Lei Chen 0031
  • Zhihai Wang
  • Yufei Kuang
  • Mingxuan Yuan
  • Jianye Hao
  • Feng Wu 0001

The efficiency of Logic Optimization (LO) has become one of the key bottlenecks in chip design. To prompt efficient LO, previous studies propose using a key scoring function to predict and prune a large number of ineffective nodes of the LO heuristics. However, the existing scoring functions struggle to balance inference efficiency, interpretability, and generalization performance, which severely hinders their application to modern LO tools. To address this challenge, we propose a novel data-driven circuit symbolic learning framework, namely CMO, to learn lightweight, interpretable, and generalizable scoring functions. The major challenge of developing CMO is to discover symbolic functions that can well generalize to unseen circuits, i.e., the circuit symbolic generalization problem. Thus, the major technical contribution of CMO is the novel Graph Enhanced Symbolic Discovery framework, which distills dark knowledge from a well-designed Graph Neural Network (GNN) to enhance the generalization capability of the learned symbolic functions. To the best of our knowledge, CMO is *the first* graph-enhanced approach for discovering lightweight and interpretable symbolic functions that can well generalize to unseen circuits in LO. Experiments on three challenging circuit benchmarks show that the *interpretable* symbolic functions learned by CMO outperform previous state-of-the-art (SOTA) GPU-based and human-designed approaches in terms of *inference efficiency* and *generalization capability*. Moreover, we integrate CMO with the Mfs2 heuristic---one of the most time-consuming LO heuristics. The empirical results demonstrate that CMO significantly improves its efficiency while keeping comparable optimization performance when executed on a CPU-based machine, achieving up to 2.5× faster runtime.

ICML Conference 2025 Conference Paper

Accelerating Large Language Model Reasoning via Speculative Search

  • Zhihai Wang
  • Jie Wang 0005
  • Jilai Pan
  • Xilin Xia
  • Huiling Zhen
  • Mingxuan Yuan
  • Jianye Hao
  • Feng Wu 0001

Tree-search-based reasoning methods have significantly enhanced the reasoning capability of large language models (LLMs) by facilitating the exploration of multiple intermediate reasoning steps, i. e. , thoughts. However, these methods suffer from substantial inference latency, as they have to generate numerous reasoning thoughts, severely limiting LLM applicability. To address this challenge, we propose a novel Speculative Search (SpecSearch) framework that significantly accelerates LLM reasoning by optimizing thought generation. Specifically, SpecSearch utilizes a small model to strategically collaborate with a large model at both thought and token levels, efficiently generating high-quality reasoning thoughts. The major pillar of SpecSearch is a novel quality-preserving rejection mechanism, which effectively filters out thoughts whose quality falls below that of the large model’s outputs. Moreover, we show that SpecSearch preserves comparable reasoning quality to the large model. Experiments on both the Qwen and Llama models demonstrate that SpecSearch significantly outperforms state-of-the-art approaches, achieving up to 2. 12$\times$ speedup with comparable reasoning quality.

NeurIPS Conference 2025 Conference Paper

Accurate KV Cache Eviction via Anchor Direction Projection for Efficient LLM Inference

  • Zijie Geng
  • Jie Wang
  • Ziqi Liu
  • Feng Ju
  • Yiming Li
  • Xing Li
  • Mingxuan Yuan
  • Jianye Hao

Key-Value (KV) cache eviction---which retains the KV pairs of the most important tokens while discarding less important ones---is a critical technique for optimizing both memory usage and inference latency in large language models (LLMs). However, existing approaches often rely on simple heuristics---such as attention weights---to measure token importance, overlooking the spatial relationships between token value states in the vector space. This often leads to suboptimal token selections and thus performance degradation. To tackle this problem, we propose a novel method, namely **AnDPro** (**An**chor **D**irection **Pro**jection), which introduces a projection-based scoring function to more accurately measure token importance. Specifically, AnDPro operates in the space of value vectors and leverages the projections of these vectors onto an *``Anchor Direction''*---the direction of the pre-eviction output---to measure token importance and guide more accurate token selection. Experiments on $16$ datasets from the LongBench benchmark demonstrate that AnDPro can maintain $96. 07\\%$ of the full cache accuracy using only $3. 44\\%$ KV cache budget, reducing KV cache budget size by $46. 0\\%$ without compromising quality compared to previous state-of-the-arts.

ICLR Conference 2025 Conference Paper

Apollo-MILP: An Alternating Prediction-Correction Neural Solving Framework for Mixed-Integer Linear Programming

  • Haoyang Liu 0002
  • Jie Wang 0005
  • Zijie Geng
  • Xijun Li
  • Yuxuan Zong
  • Fangzhou Zhu
  • Jianye Hao
  • Feng Wu 0001

Leveraging machine learning (ML) to predict an initial solution for mixed-integer linear programming (MILP) has gained considerable popularity in recent years. These methods predict a solution and fix a subset of variables to reduce the problem dimension. Then, they solve the reduced problem to obtain the final solutions. However, directly fixing variable values can lead to low-quality solutions or even infeasible reduced problems if the predicted solution is not accurate enough. To address this challenge, we propose an Alternating prediction-correction neural solving framework (Apollo-MILP) that can identify and select accurate and reliable predicted values to fix. In each iteration, Apollo-MILP conducts a prediction step for the unfixed variables, followed by a correction step to obtain an improved solution (called reference solution) through a trust-region search. By incorporating the predicted and reference solutions, we introduce a novel Uncertainty-based Error upper BOund (UEBO) to evaluate the uncertainty of the predicted values and fix those with high confidence. A notable feature of Apollo-MILP is the superior ability for problem reduction while preserving optimality, leading to high-quality final solutions. Experiments on commonly used benchmarks demonstrate that our proposed Apollo-MILP significantly outperforms other ML-based approaches in terms of solution quality, achieving over a 50% reduction in the solution gap.

NeurIPS Conference 2025 Conference Paper

AttentionPredictor: Temporal Patterns Matter for KV Cache Compression

  • Qingyue Yang
  • Jie Wang
  • Xing Li
  • Zhihai Wang
  • Chen Chen
  • Lei Chen
  • Xianzhi Yu
  • Wulong Liu

With the development of large language models (LLMs), efficient inference through Key-Value (KV) cache compression has attracted considerable attention, especially for long-context generation. To compress the KV cache, recent methods identify critical KV tokens through static modeling of attention scores. However, these methods often struggle to accurately determine critical tokens as they neglect the *temporal patterns* in attention scores, resulting in a noticeable degradation in LLM performance. To address this challenge, we propose **AttentionPredictor**, which is the **first learning-based method to directly predict attention patterns for KV cache compression and critical token identification**. Specifically, AttentionPredictor learns a lightweight, unified convolution model to dynamically capture spatiotemporal patterns and predict the next-token attention scores. An appealing feature of AttentionPredictor is that it accurately predicts the attention score and shares the unified prediction model, which consumes negligible memory, among all transformer layers. Moreover, we propose a cross-token critical cache prefetching framework that hides the token estimation time overhead to accelerate the decoding stage. By retaining most of the attention information, AttentionPredictor achieves **13$\times$** KV cache compression and **5. 6$\times$** speedup in a cache offloading scenario with comparable LLM performance, significantly outperforming the state-of-the-arts. The code is available at https: //github. com/MIRALab-USTC/LLM-AttentionPredictor.

NeurIPS Conference 2025 Conference Paper

Benchmarking End-To-End Performance of AI-Based Chip Placement Algorithms

  • Zhihai Wang
  • Zijie Geng
  • Zhaojie Tu
  • Jie Wang
  • Yuxi Qian
  • Zhexuan Xu
  • Ziyan Liu
  • Siyuan Xu

Chip placement is a critical step in the Electronic Design Automation (EDA) workflow, which aims to arrange chip modules on the canvas to optimize the performance, power, and area (PPA) metrics of final designs. Recent advances show great potential of AI-based algorithms in chip placement. However, due to the lengthy EDA workflow, evaluations of these algorithms often focus on intermediate surrogate metrics, which are computationally efficient but often misalign with the final end-to-end performance (i. e. , the final design PPA). To address this challenge, we propose to build ChiPBench, a comprehensive benchmark specifically designed to evaluate the effectiveness of AI-based algorithms in final design PPA metrics. Specifically, we generate a diverse evaluation dataset from $20$ circuits across various domains, such as CPUs, GPUs, and NPUs. We then evaluate six state-of-the-art AI-based chip placement algorithms on the dataset and conduct a thorough analysis of their placement behavior. Extensive experiments show that AI-based chip placement algorithms produce unsatisfactory final PPA results, highlighting the significant influence of often-overlooked factors like regularity and dataflow. We believe ChiPBench will effectively bridge the gap between academia and industry.

ICML Conference 2025 Conference Paper

Boosting Multi-Domain Fine-Tuning of Large Language Models through Evolving Interactions between Samples

  • Xize Liang
  • Lin Yang 0009
  • Jie Wang 0005
  • Yiyang Lu
  • Runyu Wu
  • Hanzhu Chen
  • Jianye Hao

The multi-domain fine-tuning of large language models (LLMs) confronts a notorious trade-off among abilities across domains. Existing studies attribute this trade-off to the conflicts between samples rooted in inherent semantics. Recent approaches attempt to mitigate these conflicts through the empirical investigation or heuristic strategies. However, without a fundamental understanding of interactions between samples, they yield only marginal improvements, while incurring substantial trial-and-error costs. To address this challenge, we move beyond empirical studies by modeling interactions between samples as their influence on each other’s loss, estimated using gradients. Intriguingly, we find that these interactions evolve throughout training rather than being purely determined by inherent semantics. Building on this insight, we propose EV olving I nteraction-guided C urriculum ( EVIC ), which iteratively selects samples that positively influence the overall dataset for training. By dynamically adapting the training curriculum to prioritize samples that contribute the most to the model training, EVIC effectively mitigates conflicts and improves the sample efficiency. Extensive experiments on a mixed dataset covering coding, math, and general tasks with several model architectures show that EVIC significantly outperforms all baselines across diverse capabilities.

NeurIPS Conference 2025 Conference Paper

COLA: Towards Efficient Multi-Objective Reinforcement Learning with Conflict Objective Regularization in Latent Space

  • Pengyi Li
  • Hongyao Tang
  • Yifu Yuan
  • Jianye Hao
  • Zibin Dong
  • Yan Zheng

Many real-world control problems require continual policy adjustments to balance multiple objectives, which requires the acquisition of high-quality policies to cover diverse preferences. Multi-Objective Reinforcement Learning (MORL) provides a general framework to solve such problems. However, current MORL methods suffer from high sample complexity, primarily due to the neglect of efficient knowledge sharing and conflicts in optimization with different preferences. To this end, this paper introduces a novel framework, Conflict Objective Regularization in Latent Space ( COLA ). To enable efficient knowledge sharing, COLA establishes a shared latent representation space for common knowledge, which can avoid redundant learning under different preferences. Besides, COLA introduces a regularization term for the value function to mitigate the negative effects of conflicting preferences on the value function approximation, thereby improving the accuracy of value estimation. The experimental results across various multi-objective continuous control tasks demonstrate the significant superiority of COLA over the state-of-the-art MORL baselines. Code is available at https: //github. com/yeshenpy/COLA.

ICLR Conference 2025 Conference Paper

Computing Circuits Optimization via Model-Based Circuit Genetic Evolution

  • Zhihai Wang
  • Jie Wang 0005
  • Xilin Xia
  • Dongsheng Zuo
  • Lei Chen 0031
  • Yuzhe Ma
  • Jianye Hao
  • Mingxuan Yuan

Optimizing computing circuits such as multipliers and adders is a fundamental challenge in modern integrated circuit design. Recent efforts propose formulating this optimization problem as a reinforcement learning (RL) proxy task, offering a promising approach to search high-speed and area-efficient circuit design solutions. However, we show that the RL-based formulation (proxy task) converges to a local optimal design solution (original task) due to the deceptive reward signals and incrementally localized actions in the RL-based formulation. To address this challenge, we propose a novel model-based circuit genetic evolution (MUTE) framework, which reformulates the problem as a genetic evolution process by proposing a grid-based genetic representation of design solutions. This novel formulation avoids misleading rewards by evaluating and improving generated solutions using the true objective value rather than proxy rewards. To promote globally diverse exploration, MUTE proposes a multi-granularity genetic crossover operator that recombines design substructures at varying column ranges between two grid-based genetic solutions. To the best of our knowledge, MUTE is the first to reformulate the problem as a circuit genetic evolution process, which enables effectively searching for global optimal design solutions. We evaluate MUTE on several fundamental computing circuits, including multipliers, adders, and multiply-accumulate circuits. Experiments on these circuits demonstrate that MUTE significantly Pareto-dominates state-of-the-art approaches in terms of both area and delay. Moreover, experiments demonstrate that circuits designed by MUTE well generalize to large-scale computation-intensive circuits as well.

NeurIPS Conference 2025 Conference Paper

Conditioning Matters: Training Diffusion Policies is Faster Than You Think

  • Zibin Dong
  • Yicheng Liu
  • Yinchuan Li
  • Hang Zhao
  • Jianye Hao

Diffusion policies have emerged as a mainstream paradigm for building vision-language-action (VLA) models. Although they demonstrate strong robot control capabilities, their training efficiency remains suboptimal. In this work, we identify a fundamental challenge in conditional diffusion policy training: when generative conditions are hard to distinguish, the training objective degenerates into modeling the marginal action distribution, a phenomenon we term loss collapse. To overcome this, we propose Cocos, a simple yet general solution that modifies the source distribution in the conditional flow matching to be condition-dependent. By anchoring the source distribution around semantics extracted from condition inputs, Cocos encourages stronger condition integration and prevents the loss collapse. We provide theoretical justification and extensive empirical results across simulation and real-world benchmarks. Our method achieves faster convergence and higher success rates than existing approaches, matching the performance of large-scale pre-trained VLAs using significantly fewer gradient steps and parameters. Cocos is lightweight, easy to implement, and compatible with diverse policy architectures, offering a general-purpose improvement to diffusion policy training.

NeurIPS Conference 2025 Conference Paper

CORE: Collaborative Optimization with Reinforcement Learning and Evolutionary Algorithm for Floorplanning

  • Pengyi Li
  • Shixiong Kai
  • Jianye Hao
  • Ruizhe Zhong
  • Hongyao Tang
  • Zhentao Tang
  • Mingxuan Yuan
  • Junchi Yan

Floorplanning is the initial step in the physical design process of Electronic Design Automation (EDA), directly influencing subsequent placement, routing, and final power of the chip. However, the solution space in floorplanning is vast, and current algorithms often struggle to explore it sufficiently, making them prone to getting trapped in local optima. To achieve efficient floorplanning, we propose CORE, a general and effective solution optimization framework that synergizes Evolutionary Algorithms (EAs) and Reinforcement Learning (RL) for high-quality layout search and optimization. Specifically, we propose the Clustering-based Diversified Evolutionary Search that directly perturbs layouts and evolves them based on novelty and performance. Additionally, we model the floorplanning problem as a sequential decision problem with B*-Tree representation and employ RL for efficient learning. To efficiently coordinate EAs and RL, we propose the reinforcement-driven mechanism and evolution-guided mechanism. The former accelerates population evolution through RL, while the latter guides RL learning through EAs. The experimental results on the MCNC and GSRC benchmarks demonstrate that CORE outperforms other strong baselines in terms of wirelength and area utilization metrics, achieving a 12. 9\% improvement in wirelength. CORE represents the first evolutionary reinforcement learning (ERL) algorithm for floorplanning, surpassing existing RL-based methods. The code is available at https: //github. com/yeshenpy/CORE.

ICLR Conference 2025 Conference Paper

Differentiable Integer Linear Programming

  • Zijie Geng
  • Jie Wang 0005
  • Xijun Li
  • Fangzhou Zhu
  • Jianye Hao
  • Bin Li 0025
  • Feng Wu 0001

Machine learning (ML) techniques have shown great potential in generating high-quality solutions for integer linear programs (ILPs). However, existing methods typically rely on a *supervised learning* paradigm, leading to (1) *expensive training cost* due to repeated invocations of traditional solvers to generate training labels, and (2) *plausible yet infeasible solutions* due to the misalignment between the training objective (minimizing prediction loss) and the inference objective (generating high-quality solutions). To tackle this challenge, we propose **DiffILO** (**Diff**erentiable **I**nteger **L**inear Programming **O**ptimization), an *unsupervised learning paradigm for learning to solve ILPs*. Specifically, through a novel probabilistic modeling, DiffILO reformulates ILPs---discrete and constrained optimization problems---into continuous, differentiable (almost everywhere), and unconstrained optimization problems. This reformulation enables DiffILO to simultaneously solve ILPs and train the model via straightforward gradient descent, providing two major advantages. First, it significantly reduces the training cost, as the training process does not need the aid of traditional solvers at all. Second, it facilitates the generation of feasible and high-quality solutions, as the model *learns to solve ILPs* in an end-to-end manner, thus aligning the training and inference objectives. Experiments on commonly used ILP datasets demonstrate that DiffILO not only achieves an average training speedup of $13.2$ times compared to supervised methods, but also outperforms them by generating heuristic solutions with significantly higher feasibility ratios and much better solution qualities.

ICLR Conference 2025 Conference Paper

DistRL: An Asynchronous Distributed Reinforcement Learning Framework for On-Device Control Agent

  • Taiyi Wang
  • Zhihao Wu
  • Jianheng Liu
  • Jianye Hao
  • Jun Wang 0012
  • Kun Shao

On-device control agents, especially on mobile devices, are responsible for operating mobile devices to fulfill users' requests, enabling seamless and intuitive interactions. Integrating Multimodal Large Language Models (MLLMs) into these agents enhances their ability to understand and execute complex commands, thereby improving user experience. However, fine-tuning MLLMs for on-device control presents significant challenges due to limited data availability and inefficient online training processes. This paper introduces DistRL, a novel framework designed to enhance the efficiency of online RL fine-tuning for mobile device control agents. DistRL employs centralized training and decentralized data acquisition to ensure efficient fine-tuning in the context of dynamic online interactions. Additionally, the framework is backed by our tailor-made RL algorithm, which effectively balances exploration with the prioritized utilization of collected data to ensure stable and robust training. Our experiments show that, on average, DistRL delivers a 3$\times$ improvement in training efficiency and enables training data collection 2.4$\times$ faster than the leading synchronous multi-machine methods. Notably, after training, DistRL achieves a 20\% relative improvement in success rate compared to state-of-the-art methods on general Android tasks from an open benchmark, significantly outperforming existing approaches while maintaining the same training time. These results validate DistRL as a scalable and efficient solution, offering substantial improvements in both training efficiency and agent performance for real-world, in-the-wild device control tasks.

NeurIPS Conference 2025 Conference Paper

Dynamic Configuration for Cutting Plane Separators via Reinforcement Learning on Incremental Graph

  • Mingxuan Ye
  • Jie Wang
  • Fangzhou Fangzhou
  • Zhihai Wang
  • Yufei Kuang
  • Xijun Li
  • Weilin Luo
  • Jianye Hao

Cutting planes (cuts) are essential for solving mixed-integer linear programming (MILP) problems, as they tighten the feasible solution space and accelerate the solving process. Modern MILP solvers offer diverse cutting plane separators to generate cuts, enabling users to leverage their potential complementary strengths to tackle problems with different structures. Recent machine learning approaches learn to configure separators based on problem-specific features, selecting effective separators and deactivating ineffective ones to save unnecessary computing time. However, they ignore the dynamics of separator efficacy at different stages of cut generation and struggle to adapt the configurations for the evolving problems after multiple rounds of cut generation. To address this challenge, we propose a novel dyn amic sep arator configuration ( DynSep ) method that models separator configuration in different rounds as a reinforcement learning task, making decisions based on an incremental triplet graph updated by iteratively added cuts. Specifically, we tokenize the incremental subgraphs and utilize a decoder-only Transformer as our policy to autoregressively predict when to halt separation and which separators to activate at each round. Evaluated on synthetic and large-scale real-world MILP problems, DynSep speeds up average solving time by 64% on easy and medium datasets, and reduces primal-dual gap integral within the given time limit by 16% on hard datasets. Moreover, experiments demonstrate that DynSep well generalizes to MILP instances of significantly larger sizes than those seen during training.

AAMAS Conference 2025 Conference Paper

Enhancing Graph-based Coordination with Evolutionary Algorithms for Episodic Multi-agent Reinforcement Learning

  • Kexing Peng
  • Pengyi Li
  • Jianye Hao

Multi-agent Reinforcement Learning (MARL) has made significant progress in addressing coordination problems, but two key challenges persist in environments with partial observability: limited exploration and inaccurate evaluation of individual agents. To address these challenges, we propose a novel MARL framework that integrates Evolutionary Algorithms (EAs), episodic learning, and curiosity-driven exploration to optimize the coordination of joint policies using graph-based methods, named EECG. EAs are employed for their global optimization capabilities, particularly through population diversity and a gradient-free search mechanism, to enhance policy exploration. Initially, multiple agent teams explore and learn independently while sharing a common experience pool to enable data diversity. During the evolution phase, new joint policies are generated through crossover, mutation, and pareto-based selection. During the RL phase, diverse data is used to model and update the relationships among agents via Graph Neural Networks (GNNs), which help evaluate the effectiveness of individual agents’ behaviors. GNNs treat agents as nodes and their interactions as edges, capturing coordination relationships effectively while dynamically assigning representations to nodes and edges. Furthermore, curiosity-based exploration motivates teams to discover new states, while a memory system stores high-reward experiences. We evaluated EECG on several benchmarks, including StarCraft II, SUMO autonomous driving, and the Multi-Agent Particle Environment. Our empirical results show that EECG consistently outperforms current baselines, with its components significantly contributing to faster convergence, especially by improving exploration and agent coordination. Our code is available: https: //github. com/MercyM/EECG.

IROS Conference 2025 Conference Paper

ET-Plan-Bench: Embodied Task-level Planning Benchmark Towards Spatial-Temporal Cognition with Foundation Models

  • Lingfeng Zhang
  • Yuening Wang
  • Hongjian Gu
  • Atia Hamidizadeh
  • Zhanguang Zhang
  • Yuecheng Liu
  • Yutong Wang
  • David Gamaliel Arcos Bravo

Recent advancements in Large Language Models (LLMs) have catalyzed numerous efforts to apply these technologies to embodied tasks, with a particular focus on high-level task planning and task decomposition. LLMs face challenges in understanding the physical world, especially regarding spatial, temporal, and causal relationships among objects and actions. Moreover, the current benchmarks for evaluating these relationships are limited. To further investigate this domain, we introduce a novel embodied task planning benchmark, ET-Plan-Bench. This benchmark features a controllable and diverse array of embodied tasks, varying in levels of difficulty and complexity. It is designed to evaluate two critical dimensions of LLMs’ application in embodied task understanding: spatial understanding (including relation constraints and occlusion of target objects) and temporal and causal comprehension of sequences of actions within an environment. Utilizing multi-source simulators as the backend simulator, ET-Plan-Bench provides immediate environmental feedback to LLMs, enabling dynamic interaction with the environment and the capacity for re-planning as necessary. We evaluated state-of-the-art open-source and closed-source foundational models, including GPT-4, Llama, and Mistral, using our proposed benchmark. While these models perform adequately on simple navigation tasks, their performance significantly deteriorates when con-fronted with tasks that demand a deeper understanding of spatial, temporal, and causal relationships. Consequently, our benchmark distinguishes itself as a large-scale, quantifiable, highly automated, and fine-grained diagnostic framework that presents a substantial challenge to the latest foundational models. We hope it will inspire and propel further research in embodied task planning utilizing foundational models. Code available at: https://github.com/ET-Plan-Bench/ET-Plan-Bench

NeurIPS Conference 2025 Conference Paper

High-Performance Arithmetic Circuit Optimization via Differentiable Architecture Search

  • Xilin Xia
  • Jie Wang
  • Wanbo Zhang
  • Zhihai Wang
  • Mingxuan Yuan
  • Jianye Hao
  • Feng Wu

Arithmetic circuit optimization remains a fundamental challenge in modern integrated circuit design. Recent advances have cast this problem within the Learning to Optimize (L2O) paradigm, where intelligent agents autonomously explore high-performance design spaces with encouraging results. However, existing approaches predominantly target coarse-grained architectural configurations, while the crucial interconnect optimization stage is often relegated to oversimplified proxy models or a heuristic approach. This disconnect undermines design quality, leading to suboptimal solutions in the circuit topology search space. To bridge this gap, we present **Arith-DAS**, a **D**ifferentiable **A**rchitecture **S**earch framework for **Arith**metic circuits. To the best of our knowledge, **Arith-DAS** is the first to formulate interconnect optimization within arithmetic circuits as a differentiable edge prediction problem over a multi-relational directed acyclic graph, enabling fine-grained, proxy-free optimization at the interconnection level. We evaluate **Arith-DAS** on a suite of representative arithmetic circuits, including multipliers and multiply-accumulate units. Experiments show substantial improvements over state-of-the-art L2O and conventional methods, achieving up to $\textbf{27. 05}$% gain in hypervolume of area-delay Pareto front, a standard metric for evaluating multi-objective optimization performance. Moreover, integrating our optimized arithmetic units into large-scale AI accelerators yields up to $\textbf{6. 59}$% delay reduction, demonstrating both scalability and real-world applicability.

ICML Conference 2025 Conference Paper

HyperTree Planning: Enhancing LLM Reasoning via Hierarchical Thinking

  • Runquan Gui
  • Zhihai Wang
  • Jie Wang 0005
  • Chi Ma
  • Huiling Zhen
  • Mingxuan Yuan
  • Jianye Hao
  • Defu Lian

Recent advancements have significantly enhanced the performance of large language models (LLMs) in tackling complex reasoning tasks, achieving notable success in domains like mathematical and logical reasoning. However, these methods encounter challenges with complex planning tasks, primarily due to extended reasoning steps, diverse constraints, and the challenge of handling multiple distinct sub-tasks. To address these challenges, we propose HyperTree Planning (HTP), a novel reasoning paradigm that constructs hypertree-structured planning outlines for effective planning. The hypertree structure enables LLMs to engage in hierarchical thinking by flexibly employing the divide-and-conquer strategy, effectively breaking down intricate reasoning steps, accommodating diverse constraints, and managing multiple distinct sub-tasks in a well-organized manner. We further introduce an autonomous planning framework that completes the planning process by iteratively refining and expanding the hypertree-structured planning outlines. Experiments demonstrate the effectiveness of HTP, achieving state-of-the-art accuracy on the TravelPlanner benchmark with Gemini-1. 5-Pro, resulting in a 3. 6$\times$ performance improvement over o1-preview.

AAAI Conference 2025 Conference Paper

Improving Generalization in Offline Reinforcement Learning via Latent Distribution Representation Learning

  • Da Wang
  • Lin Li
  • Wei Wei
  • Qixian Yu
  • Jianye Hao
  • Jiye Liang

Dealing with the distribution shift is a significant challenge when building offline reinforcement learning (RL) models that can generalize from a static dataset to out-of-distribution (OOD) scenarios. Previous approaches have employed pessimism or conservatism strategies. More recently, data-driven work has taken a distributional perspective, treating offline data as a domain adaptation problem. However, these methods use heuristic techniques to simulate distribution shifts, resulting in a limited diversity of artificially created distribution gaps. In this paper, we propose a novel perspective: offline datasets inherently contain multiple latent distributions, with behavior data from diverse policies potentially following different distributions and data from the same policy across various time phases also exhibiting distribution variance. We introduce the Latent Distribution Representation Learning (LAD) framework, which aims to characterize the multiple latent distributions within offline data and reduce the distribution gaps between any pair of them. LAD consists of a min-max adversarial process: it first identifies the "worst-case" distributions to enlarge the diversity of distribution gaps and then reduces these gaps to learn invariant representations for generalization. We derive a generalization error bound to support LAD theoretically and verify its effectiveness through extensive experiments.

ICLR Conference 2025 Conference Paper

LaMPlace: Learning to Optimize Cross-Stage Metrics in Macro Placement

  • Zijie Geng
  • Jie Wang 0005
  • Ziyan Liu
  • Siyuan Xu
  • Zhentao Tang
  • Shixiong Kai
  • Mingxuan Yuan
  • Jianye Hao

Machine learning techniques have shown great potential in enhancing macro placement, a critical stage in modern chip design. However, existing methods primarily focus on *online* optimization of *intermediate surrogate metrics* that are available at the current placement stage, rather than directly targeting the *cross-stage metrics*---such as the timing performance---that measure the final chip quality. This is mainly because of the high computational costs associated with performing post-placement stages for evaluating such metrics, making the *online* optimization impractical. Consequently, these optimizations struggle to align with actual performance improvements and can even lead to severe manufacturing issues. To bridge this gap, we propose **LaMPlace**, which **L**earns **a** **M**ask for optimizing cross-stage metrics in macro placement. Specifically, LaMPlace trains a predictor on *offline* data to estimate these *cross-stage metrics* and then leverages the predictor to quickly generate a mask, i.e., a pixel-level feature map that quantifies the impact of placing a macro in each chip grid location on the design metrics. This mask essentially acts as a fast evaluator, enabling placement decisions based on *cross-stage metrics* rather than *intermediate surrogate metrics*. Experiments on commonly used benchmarks demonstrate that LaMPlace significantly improves the chip quality across several key design metrics, achieving an average improvement of 9.6\%, notably 43.0\% and 30.4\% in terms of WNS and TNS, respectively, which are two crucial cross-stage metrics that reflect the final chip quality in terms of the timing performance.

NeurIPS Conference 2025 Conference Paper

LaRes: Evolutionary Reinforcement Learning with LLM-based Adaptive Reward Search

  • Pengyi Li
  • Hongyao Tang
  • Jinbin Qiao
  • Yan Zheng
  • Jianye Hao

The integration of evolutionary algorithms (EAs) with reinforcement learning (RL) has shown superior performance compared to standalone methods. However, previous research focuses on exploration in policy parameter space, while overlooking the reward function search. To bridge this gap, we propose LaRes, a novel hybrid framework that achieves efficient policy learning through reward function search. LaRes leverages large language models (LLMs) to generate the reward function population, guiding RL in policy learning. The reward functions are evaluated by the policy performance and improved through LLMs. To improve sample efficiency, LaRes employs a shared experience buffer that collects experiences from all policies, with each experience containing rewards from all reward functions. Upon reward function updates, the rewards of experiences are relabeled, enabling efficient use of historical data. Furthermore, we introduce a Thompson sampling-based selection mechanism that enables more efficient elite interaction. To prevent policy collapse when improving reward functions, we propose the reward scaling and parameter constraint mechanisms to efficiently coordinate reward search with policy learning. Across both initialized and non-initialized settings, LaRes consistently achieves state-of-the-art performance, outperforming strong baselines in both sample efficiency and final performance. The code is available at https: //github. com/yeshenpy/LaRes.

ICLR Conference 2025 Conference Paper

Lightweight Neural App Control

  • Filippos Christianos
  • Georgios Papoudakis
  • Thomas Coste
  • Jianye Hao
  • Jun Wang 0012
  • Kun Shao

This paper introduces a novel mobile phone control architecture, Lightweight Multi-modal App Control (LiMAC), for efficient interactions and control across various Android apps. LiMAC takes as input a textual goal and a sequence of past mobile observations, such as screenshots and corresponding UI trees, to generate precise actions. To address the computational constraints inherent to smartphones, we introduce a small Action Transformer (AcT) integrated with a fine-tuned vision-language model (VLM) for real-time decision-making and task execution. We evaluate LiMAC on two open-source mobile control datasets, demonstrating the superior performance of our small-form-factor approach against fine-tuned versions of open-source VLMs, such as Florence2 and Qwen2-VL. It also significantly outperforms prompt engineering baselines utilising closed-source foundation models like GPT-4o. More specifically, LiMAC increases the overall action accuracy by up to 19% compared to fine-tuned VLMs, and up to 42% compared to prompt-engineering baselines.

NeurIPS Conference 2025 Conference Paper

LogicTree: Improving Complex Reasoning of LLMs via Instantiated Multi-step Synthetic Logical Data

  • Zehao Wang
  • Lin Yang
  • Jie Wang
  • Kehan Wang
  • Hanzhu Chen
  • Bin Wang
  • Jianye Hao
  • Defu Lian

Despite their remarkable performance on various tasks, Large Language Models (LLMs) still struggle with logical reasoning, particularly in complex and multi-step reasoning processes. Among various efforts to enhance LLMs' reasoning capabilities, synthesizing large-scale, high-quality logical reasoning datasets has emerged as a promising direction. However, existing methods often rely on predefined templates for logical reasoning data generation, limiting their adaptability to real-world scenarios. To address the limitation, we propose LogicTree, a novel framework for efficiently synthesizing multi-step logical reasoning dataset that excels in both complexity and instantiation. By iteratively searching for applicable logic rules based on structural pattern matching to perform backward deduction, LogicTree constructs multi-step logic trees that capture complex reasoning patterns. Furthermore, we employ a two-stage LLM-based approach to instantiate various real-world scenarios for each logic tree, generating consistent real-world reasoning processes that carry contextual significance. This helps LLMs develop generalizable logical reasoning abilities across diverse scenarios rather than merely memorizing templates. Experiments on multiple benchmarks demonstrate that our approach achieves an average improvement of 9. 4\% in accuracy on complex logical reasoning tasks.

ICML Conference 2025 Conference Paper

MODULI: Unlocking Preference Generalization via Diffusion Models for Offline Multi-Objective Reinforcement Learning

  • Yifu Yuan
  • Zhenrui Zheng
  • Zibin Dong
  • Jianye Hao

Multi-objective Reinforcement Learning (MORL) seeks to develop policies that simultaneously optimize multiple conflicting objectives, but it requires extensive online interactions. Offline MORL provides a promising solution by training on pre-collected datasets to generalize to any preference upon deployment. However, real-world offline datasets are often conservatively and narrowly distributed, failing to comprehensively cover preferences, leading to the emergence of out-of-distribution (OOD) preference areas. Existing offline MORL algorithms exhibit poor generalization to OOD preferences, resulting in policies that do not align with preferences. Leveraging the excellent expressive and generalization capabilities of diffusion models, we propose MODULI (Multi-objective Diffusion Planner with Sliding Guidance), which employs a preference-conditioned diffusion model as a planner to generate trajectories that align with various preferences and derive action for decision-making. To achieve accurate generation, MODULI introduces two return normalization methods under diverse preferences for refining guidance. To further enhance generalization to OOD preferences, MODULI proposes a novel sliding guidance mechanism, which involves training an additional slider adapter to capture the direction of preference changes. Incorporating the slider, it transitions from in-distribution (ID) preferences to generating OOD preferences, patching, and extending the incomplete Pareto front. Extensive experiments on the D4MORL benchmark demonstrate that our algorithm outperforms state-of-the-art Offline MORL baselines, exhibiting excellent generalization to OOD preferences.

NeurIPS Conference 2025 Conference Paper

OptiTree: Hierarchical Thoughts Generation with Tree Search for LLM Optimization Modeling

  • Haoyang Liu
  • Jie Wang
  • Yuyang Cai
  • Xiongwei Han
  • Yufei Kuang
  • Jianye Hao

Optimization modeling is one of the most crucial but technical parts of operations research (OR). To automate the modeling process, existing works have leveraged large language models (LLMs), prompting them to break down tasks into steps for generating variables, constraints, and objectives. However, due to the highly complex mathematical structures inherent in OR problems, standard fixed-step decomposition often fails to achieve high performance. To address this challenge, we introduce OptiTree, a novel tree search approach designed to enhance modeling capabilities for complex problems through adaptive problem decomposition into simpler subproblems. Specifically, we develop a modeling tree that organizes a wide range of OR problems based on their hierarchical problem taxonomy and complexity, with each node representing a problem category and containing relevant high-level modeling thoughts. Given a problem to model, we recurrently search the tree to identify a series of simpler subproblems and synthesize the global modeling thoughts by adaptively integrating the hierarchical thoughts. Experiments show that OptiTree significantly improves the modeling accuracy compared to the state-of-the-art, achieving over 10% improvements on the challenging benchmarks.

ICML Conference 2025 Conference Paper

R*: Efficient Reward Design via Reward Structure Evolution and Parameter Alignment Optimization with Large Language Models

  • Pengyi Li 0001
  • Jianye Hao
  • Hongyao Tang
  • Yifu Yuan
  • Jinbin Qiao
  • Zibin Dong
  • Yan Zheng 0002

Reward functions are crucial for policy learning. Large Language Models (LLMs), with strong coding capabilities and valuable domain knowledge, provide an automated solution for high-quality reward design. However, code-based reward functions require precise guiding logic and parameter configurations within a vast design space, leading to low optimization efficiency. To address the challenges, we propose an efficient automated reward design framework, called R, which decomposes reward design into two parts: reward structure evolution and parameter alignment optimization. To design high-quality reward structures, R maintains a reward function population and modularizes the functional components. LLMs are employed as the mutation operator, and module-level crossover is proposed to facilitate efficient exploration and exploitation. To design more efficient reward parameters, R first leverages LLMs to generate multiple critic functions for trajectory comparison and annotation. Based on these critics, a voting mechanism is employed to collect the trajectory segments with high-confidence labels. These labeled segments are then used to refine the reward function parameters through preference learning. Experiments on diverse robotic control tasks demonstrate that R outperforms strong baselines in both reward design efficiency and quality, surpassing human-designed reward functions.

IJCAI Conference 2025 Conference Paper

Reinforced In-Context Black-Box Optimization

  • Lei Song
  • Chen-Xiao Gao
  • Ke Xue
  • Chenyang Wu
  • Dong Li
  • Jianye Hao
  • Zongzhang Zhang
  • Chao Qian

Black-Box Optimization (BBO) has found successful applications in many fields of science and engineering. Recently, there has been a growing interest in meta-learning particular components of BBO algorithms to speed up optimization and get rid of tedious hand-crafted heuristics. As an extension, learning the entire algorithm from data requires the least labor from experts and can provide the most flexibility. In this paper, we propose RIBBO, a method to reinforce-learn a BBO algorithm from offline data in an end-to-end fashion. RIBBO employs expressive sequence models to learn the optimization histories produced by multiple behavior algorithms and tasks, leveraging the in-context learning ability of large models to extract task information and make decisions accordingly. Central to our method is to augment the optimization histories with regret-to-go tokens, which are designed to represent the performance of an algorithm based on cumulative regret over the future part of the histories. The integration of regret-to-go tokens enables RIBBO to automatically generate sequences of query points that are positively correlated to the user-desired regret, verified by its universally good empirical performance on diverse problems, including BBO benchmark, hyper-parameter optimization, and robot control problems.

ICLR Conference 2025 Conference Paper

Spa-Bench: a comprehensive Benchmark for Smartphone Agent Evaluation

  • Jingxuan Chen
  • Derek Yuen
  • Bin Xie
  • Yuhao Yang 0008
  • Gongwei Chen
  • Zhihao Wu
  • Li Yixing
  • Xurui Zhou

Smartphone agents are increasingly important for helping users control devices efficiently, with (Multimodal) Large Language Model (MLLM)-based approaches emerging as key contenders. Fairly comparing these agents is essential but challenging, requiring a varied task scope, the integration of agents with different implementations, and a generalisable evaluation pipeline to assess their strengths and weaknesses. In this paper, we present SPA-Bench, a comprehensive SmartPhone Agent Benchmark designed to evaluate (M)LLM-based agents in an interactive environment that simulates real-world conditions. SPA-Bench offers three key contributions: (1) A diverse set of tasks covering system and third-party apps in both English and Chinese, focusing on features commonly used in daily routines; (2) A plug-and-play framework enabling real-time agent interaction with Android devices, integrating over ten agents with the flexibility to add more; (3) A novel evaluation pipeline that automatically assesses agent performance across multiple dimensions, encompassing seven metrics related to task completion and resource consumption. Our extensive experiments across tasks and agents reveal challenges like interpreting mobile user interfaces, action grounding, memory retention, and execution costs. We propose future research directions to ease these difficulties, moving closer to real-world smartphone agent applications.

ICML Conference 2025 Conference Paper

STAR: Learning Diverse Robot Skill Abstractions through Rotation-Augmented Vector Quantization

  • Hao Li
  • Qi Lv 0001
  • Rui Shao 0001
  • Xiang Deng 0002
  • Yinchuan Li
  • Jianye Hao
  • Liqiang Nie

Transforming complex actions into discrete skill abstractions has demonstrated strong potential for robotic manipulation. Existing approaches mainly leverage latent variable models, e. g. , VQ-VAE, to learn skill abstractions through learned vectors (codebooks), while they suffer from codebook collapse and modeling the causal relationship between learned skills. To address these limitations, we present S kill T raining with A ugmented R otation ( STAR ), a framework that advances both skill learning and composition to complete complex behaviors. Specifically, to prevent codebook collapse, we devise rotation-augmented residual skill quantization (RaRSQ). It encodes relative angles between encoder outputs into the gradient flow by rotation-based gradient mechanism. Points within the same skill code are forced to be either pushed apart or pulled closer together depending on gradient directions. Further, to capture the casual relationship between skills, we present causal skill transformer (CST) which explicitly models dependencies between skill representations through an autoregressive mechanism for coherent action generation. Extensive experiments demonstrate the superiority of STAR on both LIBERO benchmark and realworld tasks, with around 12% improvement over the baselines.

NeurIPS Conference 2025 Conference Paper

Succeed or Learn Slowly: Sample Efficient Off-Policy Reinforcement Learning for Mobile App Control

  • Georgios Papoudakis
  • Thomas Coste
  • Jianye Hao
  • Jun Wang
  • Kun Shao

Reinforcement learning (RL) using foundation models for policy approximations in multi-turn tasks remains challenging. We identify two main limitations related to sparse reward settings and policy gradient updates, based on which we formulate a key insight: updates from positive samples with high returns typically do not require policy regularisation, whereas updates from negative samples, reflecting undesirable behaviour, can harm model performance. This paper introduces Succeed or Learn Slowly (SoLS), a novel off-policy RL algorithm evaluated on mobile app control tasks. SoLS improves sample efficiency when fine-tuning foundation models for user interface navigation via a modified off-policy actor-critic approach, applying direct policy updates for positive samples and conservative, regularised updates for negative ones to prevent model degradation. We augment SoLS with Successful Transition Replay (STR), which prioritises learning from successful interactions, further improving sample efficiency. We evaluate SoLS on the AndroidWorld benchmark, where it significantly outperforms existing methods (at least 17\% relative increase), including prompt-engineering and RL approaches, while requiring substantially fewer computational resources than GPT-4o-based methods with 5-60x faster inference.

AAAI Conference 2025 Conference Paper

SWAMamba: A Sliding Window Attention Mamba Framework for Predicting Translation Elongation Rates

  • Xi Zeng
  • Fei Ni
  • Shaoqing Jiao
  • Dazhi Lu
  • Jianye Hao
  • Jiajie Peng

Translation elongation is essential for cellular proteostasis and is implicated in cancer and neurodegeneration. Accurately predicting the rate of ribosome elongation in each codon (also called ribosomal A site) on mRNA is important for understanding and modulating protein synthesis. However, predicting elongation rates is challenging due to the trade-off between capturing distal codon interactions and focusing on proximal codon effects at the A site. Approaches capturing distal codon interactions in the coding sequences (CDS) of mRNA fail to effectively differentiate critical regions (codons near the A site) due to insufficient effective mechanisms for focusing on these regions. Conversely, due to the limitations of models when handling long mRNA sequences, some methods simplify inputs by conditioning solely on proximal codons surrounding the A site, leading to the loss of important information from distal codons. To address this issue, we leverage Mamba's success in capturing long-range dependencies to enable the consideration of distant codons' impact on the A site. Additionally, we introduce a sliding window attention mechanism to emphasize the proximal codons around the A site during ribosome elongation. Building on these advancements, we present Sliding Window Attention Mamba (SWAMamba), a novel framework that simultaneously leverages both proximal and distal codon effects on the A site. We conduct comprehensive evaluations on ribosome data across four species and find that SWAMamba significantly outperformed current state-of-the-art methods in predicting translation elongation rates.

IJCAI Conference 2025 Conference Paper

The Graph’s Apprentice: Teaching an LLM Low-Level Knowledge for Circuit Quality Estimation

  • Reza Moravej
  • Saurabh Bodhe
  • Zhanguang Zhang
  • Didier Chételat
  • Dimitrios Tsaras
  • Yingxue Zhang
  • Hui-Ling Zhen
  • Jianye Hao

Logic synthesis is a crucial phase in the circuit design process, responsible for transforming hardware description language (HDL) designs into optimized netlists. However, traditional logic synthesis methods are computationally intensive, restricting their iterative use in refining chip designs. Recent advancements in large language models (LLMs), particularly those fine-tuned on programming languages, present a promising alternative. This work proposes augmenting LLMs with predictor networks trained to estimate circuit quality directly from HDL code. To enhance performance, the model is regularized using embeddings from graph neural networks (GNNs) trained on Look-Up Table (LUT) graphs, thereby incorporating lower-level circuit insights. The proposed method demonstrates superior performance compared to existing graph-based RTL-level estimation techniques on the established benchmark OpenABCD, while providing instant feedback on HDL code quality.

ICML Conference 2025 Conference Paper

Trajectory World Models for Heterogeneous Environments

  • Shaofeng Yin
  • Jialong Wu 0001
  • Siqiao Huang
  • Xingjian Su
  • Xu He
  • Jianye Hao
  • Mingsheng Long

Heterogeneity in sensors and actuators across environments poses a significant challenge to building large-scale pre-trained world models on top of this low-dimensional sensor information. In this work, we explore pre-training world models for heterogeneous environments by addressing key transfer barriers in both data diversity and model flexibility. We introduce UniTraj, a unified dataset comprising over one million trajectories from 80 environments, designed to scale data while preserving critical diversity. Additionally, we propose TrajWorld, a novel architecture capable of flexibly handling varying sensor and actuator information and capturing environment dynamics in-context. Pre-training TrajWorld on UniTraj yields substantial gains in transition prediction, achieves a new state-of-the-art for off-policy evaluation, and also delivers superior online performance of model predictive control. To the best of our knowledge, this work, for the first time, demonstrates the transfer benefits of world models across heterogeneous and complex control environments. Code and data are available at https: //github. com/thuml/TrajWorld.

NeurIPS Conference 2025 Conference Paper

Uncertainty-quantified Rollout Policy Adaptation for Unlabelled Cross-domain Video Temporal Grounding

  • Jian Hu
  • Zixu Cheng
  • Shaogang Gong
  • Isabel Guan
  • Jianye Hao
  • Jun Wang
  • Kun Shao

Video Temporal Grounding (TG) aims to temporally locate video segments matching a natural language description (a query) in a long video. While Vision-Language Models (VLMs) are effective at holistic semantic matching, they often struggle with fine-grained temporal localisation. Recently, Group Relative Policy Optimisation (GRPO) reformulates the inference process as a reinforcement learning task, enabling fine-grained grounding and achieving strong in-domain performance. However, GRPO relies on labelled data, making it unsuitable in unlabelled domains. Moreover, because videos are large and expensive to store and process, performing full-scale adaptation introduces prohibitive latency and computational overhead, making it impractical for real-time deployment. To overcome both problems, we introduce a Data-Efficient Unlabelled Cross-domain Temporal Grounding method, from which a model is first trained on a labelled source domain, then adapted to a target domain using only a small number of {\em unlabelled videos from the target domain}. This approach eliminates the need for target annotation and keeps both computational and storage overhead low enough to run in real time. Specifically, we introduce \textbf{U}ncertainty-quantified \textbf{R}ollout \textbf{P}olicy \textbf{A}daptation (\textbf{URPA}) for cross-domain knowledge transfer in learning video temporal grounding without target labels. URPA generates multiple candidate predictions using GRPO rollouts, averages them to form a pseudo label, and estimates confidence from the variance across these rollouts. This confidence then weights the training rewards, guiding the model to focus on reliable supervision. Experiments on three datasets across six cross-domain settings show that URPA generalises well using only a few unlabelled target videos. Codes are given in supplemental materials.

ICML Conference 2024 Conference Paper

A Circuit Domain Generalization Framework for Efficient Logic Synthesis in Chip Design

  • Zhihai Wang
  • Lei Chen 0031
  • Jie Wang 0005
  • Yinqi Bai
  • Xing Li 0023
  • Xijun Li
  • Mingxuan Yuan
  • Jianye Hao

Logic Synthesis (LS) plays a vital role in chip design. A key task in LS is to simplify circuits—modeled by directed acyclic graphs (DAGs)—with functionality-equivalent transformations. To tackle this task, many LS heuristics apply transformations to subgraphs—rooted at each node on an input DAG—sequentially. However, we found that a large number of transformations are ineffective, which makes applying these heuristics highly time-consuming. In particular, we notice that the runtime of the Resub and Mfs2 heuristics often dominates the overall runtime of LS optimization processes. To address this challenge, we propose a novel data-driven LS heuristic paradigm, namely PruneX, to reduce ineffective transformations. The major challenge of developing PruneX is to learn models that well generalize to unseen circuits, i. e. , the out-of-distribution (OOD) generalization problem. Thus, the major technical contribution of PruneX is the novel circuit domain generalization framework, which learns domain-invariant representations based on the transformation-invariant domain-knowledge. To the best of our knowledge, PruneX is the first approach to tackle the OOD problem in LS heuristics. We integrate PruneX with the aforementioned Resub and Mfs2 heuristics. Experiments demonstrate that PruneX significantly improves their efficiency while keeping comparable optimization performance on industrial and very large-scale circuits, achieving up to $3. 1\times$ faster runtime.

ICML Conference 2024 Conference Paper

A Hierarchical Adaptive Multi-Task Reinforcement Learning Framework for Multiplier Circuit Design

  • Zhihai Wang
  • Jie Wang 0005
  • Dongsheng Zuo
  • Yunjie Ji
  • Xilin Xia
  • Yuzhe Ma
  • Jianye Hao
  • Mingxuan Yuan

Multiplier design—which aims to explore a large combinatorial design space to simultaneously optimize multiple conflicting objectives—is a fundamental problem in the integrated circuits industry. Although traditional approaches tackle the multi-objective multiplier optimization problem by manually designed heuristics, reinforcement learning (RL) offers a promising approach to discover high-speed and area-efficient multipliers. However, the existing RL-based methods struggle to find Pareto-optimal circuit designs for all possible preferences, i. e. , weights over objectives, in a sample-efficient manner. To address this challenge, we propose a novel hierarchical adaptive (HAVE) multi-task reinforcement learning framework. The hierarchical framework consists of a meta-agent to generate diverse multiplier preferences, and an adaptive multi-task agent to collaboratively optimize multipliers conditioned on the dynamic preferences given by the meta-agent. To the best of our knowledge, HAVE is the first to well approximate Pareto-optimal circuit designs for the entire preference space with high sample efficiency. Experiments on multipliers across a wide range of input widths demonstrate that HAVE significantly Pareto-dominates state-of-the-art approaches, achieving up to 28% larger hypervolume. Moreover, experiments demonstrate that multipliers designed by HAVE can well generalize to large-scale computation-intensive circuits.

AAMAS Conference 2024 Conference Paper

A Trajectory Perspective on the Role of Data Sampling Techniques in Offline Reinforcement Learning

  • Jinyi Liu
  • Yi Ma
  • Jianye Hao
  • Yujing Hu
  • Yan Zheng
  • Tangjie Lv
  • Changjie Fan

In recent years, offline reinforcement learning (RL) algorithms have gained considerable attention. However, the role of data sampling techniques in offline RL has been somewhat overlooked, despite their potential to enhance online RL performance. Recent research in offline RL indicates that applying sampling techniques directly to state-transitions does not consistently improve performance. Therefore, to better leverage limited offline trajectory data, we investigate the impact of data sampling processes on offline RL algorithms from a trajectory perspective. In this paper, we introduce a memory technique, (Prioritized) Trajectory Replay (TR/PTR), to facilitate trajectory data storage and sampling. Building on TR, we delve into the potential of trajectory backward sampling, a method that has already proven effective in online RL, in the offline RL domain. Furthermore, to improve the sampling efficiency, we examine the influence of prioritized sampling based on various trajectory priority metrics on offline training. Integrating with existing algorithms, our findings demonstrate that data sampling and updates based on vanilla TR can contribute to more stable training. Also, our proposed 13 trajectory priority metrics for PTR exhibit outstanding performance on their respective applicable types of dataset, with the best-case scenario resulting in performance improvements exceeding 25%. These performance gains are achieved at a slight extra cost during the data sampling process, highlighting the significant advantages of trajectory-based data sampling for offline RL. †Corresponding author: Yan Zheng (yanzheng@tju. edu. cn). ∗This work is done when Jinyi Liu was intern in NetEase Fuxi AI Lab. This work is licensed under a Creative Commons Attribution International 4. 0 License. Proc. of the 23rd International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2024), N. Alechina, V. Dignum, M. Dastani, J. S. Sichman (eds.), May 6 – 10, 2024, Auckland, New Zealand. © 2024 International Foundation for Autonomous Agents and Multiagent Systems (www. ifaamas. org).

AAAI Conference 2024 Conference Paper

A Transfer Approach Using Graph Neural Networks in Deep Reinforcement Learning

  • Tianpei Yang
  • Heng You
  • Jianye Hao
  • Yan Zheng
  • Matthew E. Taylor

Transfer learning (TL) has shown great potential to improve Reinforcement Learning (RL) efficiency by leveraging prior knowledge in new tasks. However, much of the existing TL research focuses on transferring knowledge between tasks that share the same state-action spaces. Further, transfer from multiple source tasks that have different state-action spaces is more challenging and needs to be solved urgently to improve the generalization and practicality of the method in real-world scenarios. This paper proposes TURRET (Transfer Using gRaph neuRal nETworks), to utilize the generalization capabilities of Graph Neural Networks (GNNs) to facilitate efficient and effective multi-source policy transfer learning in the state-action mismatch setting. TURRET learns a semantic representation by accounting for the intrinsic property of the agent through GNNs, which leads to a unified state embedding space for all tasks. As a result, TURRET achieves more efficient transfer with strong generalization ability between different tasks and can be easily combined with existing Deep RL algorithms. Experimental results show that TURRET significantly outperforms other TL methods on multiple continuous action control tasks, successfully transferring across robots with different state-action spaces.

ICLR Conference 2024 Conference Paper

AlignDiff: Aligning Diverse Human Preferences via Behavior-Customisable Diffusion Model

  • Zibin Dong
  • Yifu Yuan
  • Jianye Hao
  • Fei Ni 0001
  • Yao Mu 0001
  • Yan Zheng 0002
  • Yujing Hu
  • Tangjie Lv

Aligning agent behaviors with diverse human preferences remains a challenging problem in reinforcement learning (RL), owing to the inherent abstractness and mutability of human preferences. To address these issues, we propose AlignDiff, a novel framework that leverages RLHF to quantify human preferences, covering abstractness, and utilizes them to guide diffusion planning for zero-shot behavior customizing, covering mutability. AlignDiff can accurately match user-customized behaviors and efficiently switch from one to another. To build the framework, we first establish the multi-perspective human feedback datasets, which contain comparisons for the attributes of diverse behaviors, and then train an attribute strength model to predict quantified relative strengths. After relabeling behavioral datasets with relative strengths, we proceed to train an attribute-conditioned diffusion model, which serves as a planner with the attribute strength model as a director for preference aligning at the inference phase. We evaluate AlignDiff on various locomotion tasks and demonstrate its superior performance on preference matching, switching, and covering compared to other baselines. Its capability of completing unseen downstream tasks under human instructions also showcases the promising potential for human-AI collaboration. More visualization videos are released on https://aligndiff.github.io/.

NeurIPS Conference 2024 Conference Paper

CleanDiffuser: An Easy-to-use Modularized Library for Diffusion Models in Decision Making

  • Zibin Dong
  • Yifu Yuan
  • Jianye Hao
  • Fei Ni
  • Yi Ma
  • Pengyi Li
  • Yan Zheng

Leveraging the powerful generative capability of diffusion models (DMs) to build decision-making agents has achieved extensive success. However, there is still a demand for an easy-to-use and modularized open-source library that offers customized and efficient development for DM-based decision-making algorithms. In this work, we introduce CleanDiffuser, the first DM library specifically designed for decision-making algorithms. By revisiting the roles of DMs in the decision-making domain, we identify a set of essential sub-modules that constitute the core of CleanDiffuser, allowing for the implementation of various DM algorithms with simple and flexible building blocks. To demonstrate the reliability and flexibility of CleanDiffuser, we conduct comprehensive evaluations of various DM algorithms implemented with CleanDiffuser across an extensive range of tasks. The analytical experiments provide a wealth of valuable design choices and insights, reveal opportunities and challenges, and lay a solid groundwork for future research. CleanDiffuser will provide long-term support to the decision-making community, enhancing reproducibility and fostering the development of more robust solutions.

NeurIPS Conference 2024 Conference Paper

DiffuserLite: Towards Real-time Diffusion Planning

  • Zibin Dong
  • Jianye Hao
  • Yifu Yuan
  • Fei Ni
  • Yitian Wang
  • Pengyi Li
  • Yan Zheng

Diffusion planning has been recognized as an effective decision-making paradigm in various domains. The capability of generating high-quality long-horizon trajectories makes it a promising research direction. However, existing diffusion planning methods suffer from low decision-making frequencies due to the expensive iterative sampling cost. To alleviate this, we introduce DiffuserLite, a super fast and lightweight diffusion planning framework, which employs a planning refinement process (PRP) to generate coarse-to-fine-grained trajectories, significantly reducing the modeling of redundant information and leading to notable increases in decision-making frequency. Our experimental results demonstrate that DiffuserLite achieves a decision-making frequency of $122. 2$Hz ($112. 7$x faster than predominant frameworks) and reaches state-of-the-art performance on D4RL, Robomimic, and FinRL benchmarks. In addition, DiffuserLite can also serve as a flexible plugin to increase the decision-making frequency of other diffusion planning algorithms, providing a structural design reference for future works. More details and visualizations are available at https: //diffuserlite. github. io/.

AAMAS Conference 2024 Conference Paper

ENOTO: Improving Offline-to-Online Reinforcement Learning with Q-Ensembles

  • Kai Zhao
  • Jianye Hao
  • Yi Ma
  • Jinyi Liu
  • Yan Zheng
  • Zhaopeng Meng

Offline reinforcement learning (RL) is a learning paradigm where an agent learns from a fixed dataset of experience. However, learning solely from a static dataset can limit the performance due to the lack of exploration. To overcome it, offline-to-online RL combines offline pre-training with online fine-tuning, which enables the agent to further refine its policy by interacting with the environment in real-time. Despite its benefits, existing offline-to-online RL methods suffer from performance degradation and slow improvement during the online phase. To tackle these challenges, we propose a novel framework called ENsemble-based Offline-To- Online (ENOTO) RL. By increasing the number of Q-networks, we seamlessly bridge offline pre-training and online fine-tuning without degrading performance. Moreover, to expedite online performance enhancement, we appropriately loosen the pessimism of Q-value estimation and incorporate ensemble-based exploration mechanisms into our framework. Experimental results demonstrate that ENOTO can substantially improve the training stability, learning efficiency, and final performance of existing offline RL methods during online fine-tuning on a range of locomotion tasks, significantly outperforming existing offline-to-online RL methods.

IJCAI Conference 2024 Conference Paper

ENOTO: Improving Offline-to-Online Reinforcement Learning with Q-Ensembles

  • Kai Zhao
  • Jianye Hao
  • Yi Ma
  • Jinyi Liu
  • Yan Zheng
  • Zhaopeng Meng

Offline reinforcement learning (RL) is a learning paradigm where an agent learns from a fixed dataset of experience. However, learning solely from a static dataset can limit the performance due to the lack of exploration. To overcome it, offline-to-online RL combines offline pre-training with online fine-tuning, which enables the agent to further refine its policy by interacting with the environment in real-time. Despite its benefits, existing offline-to-online RL methods suffer from performance degradation and slow improvement during the online phase. To tackle these challenges, we propose a novel framework called ENsemble-based Offline-To-Online (ENOTO) RL. By increasing the number of Q-networks, we seamlessly bridge offline pre-training and online fine-tuning without degrading performance. Moreover, to expedite online performance enhancement, we appropriately loosen the pessimism of Q-value estimation and incorporate ensemble-based exploration mechanisms into our framework. Experimental results demonstrate that ENOTO can substantially improve the training stability, learning efficiency, and final performance of existing offline RL methods during online fine-tuning on a range of locomotion and navigation tasks, significantly outperforming existing offline-to-online RL methods.

ICML Conference 2024 Conference Paper

EvoRainbow: Combining Improvements in Evolutionary Reinforcement Learning for Policy Search

  • Pengyi Li 0001
  • Yan Zheng 0002
  • Hongyao Tang
  • Xian Fu
  • Jianye Hao

Both Evolutionary Algorithms (EAs) and Reinforcement Learning (RL) have demonstrated powerful capabilities in policy search with different principles. A promising direction is to combine the respective strengths of both for efficient policy optimization. To this end, many works have proposed various mechanisms to integrate EAs and RL. However, it is still unclear which of these mechanisms are complementary and can be fully combined. In this paper, we revisit different mechanisms from five perspectives: 1) Interaction Mode, 2) Individual Architecture, 3) EAs and operators, 4) Impact of EA on RL, and 5) Fitness Surrogate and Usage. We evaluate the effectiveness of each mechanism and experimentally analyze the reasons for the more effective mechanisms. Using the most effective mechanisms, we develop EvoRainbow and EvoRainbow-Exp, which outperform strong baselines and provide state-of-the-art performance across various tasks with distinct characteristics. To promote community development, we release the code on https: //github. com/yeshenpy/EvoRainbow.

NeurIPS Conference 2024 Conference Paper

FlexPlanner: Flexible 3D Floorplanning via Deep Reinforcement Learning in Hybrid Action Space with Multi-Modality Representation

  • Ruizhe Zhong
  • Xingbo Du
  • Shixiong Kai
  • Zhentao Tang
  • Siyuan Xu
  • Jianye Hao
  • Mingxuan Yuan
  • Junchi Yan

In the Integrated Circuit (IC) design flow, floorplanning (FP) determines the position and shape of each block. Serving as a prototype for downstream tasks, it is critical and establishes the upper bound of the final PPA (Power, Performance, Area). However, with the emergence of 3D IC with stacked layers, existing methods are not flexible enough to handle the versatile constraints. Besides, they typically face difficulties in aligning the cross-die modules in 3D ICs due to their heuristic representations, which could potentially result in severe data transfer failures. To address these issues, we propose FlexPlanner, a flexible learning-based method in hybrid action space with multi-modality representation to simultaneously handle position, aspect ratio, and alignment of blocks. To our best knowledge, FlexPlanner is the first learning-based approach to discard heuristic-based search in the 3D FP task. Thus, the solution space is not limited by the heuristic floorplanning representation, allowing for significant improvements in both wirelength and alignment scores. Specifically, FlexPlanner models 3D FP based on multi-modalities, including vision, graph, and sequence. To address the non-trivial heuristic-dependent issue, we design a sophisticated policy network with hybrid action space and asynchronous layer decision mechanism that allow for determining the versatile properties of each block. Experiments on public benchmarks MCNC and GSRC show the effectiveness. We significantly improve the alignment score from 0. 474 to 0. 940 and achieve an average reduction of 16% in wirelength. Moreover, our method also demonstrates zero-shot transferability on unseen circuits.

ICML Conference 2024 Conference Paper

HarmonyDream: Task Harmonization Inside World Models

  • Haoyu Ma
  • Jialong Wu 0001
  • Ningya Feng
  • Chenjun Xiao
  • Dong Li 0016
  • Jianye Hao
  • Jianmin Wang 0001
  • Mingsheng Long

Model-based reinforcement learning (MBRL) holds the promise of sample-efficient learning by utilizing a world model, which models how the environment works and typically encompasses components for two tasks: observation modeling and reward modeling. In this paper, through a dedicated empirical investigation, we gain a deeper understanding of the role each task plays in world models and uncover the overlooked potential of sample-efficient MBRL by mitigating the domination of either observation or reward modeling. Our key insight is that while prevalent approaches of explicit MBRL attempt to restore abundant details of the environment via observation models, it is difficult due to the environment’s complexity and limited model capacity. On the other hand, reward models, while dominating implicit MBRL and adept at learning compact task-centric dynamics, are inadequate for sample-efficient learning without richer learning signals. Motivated by these insights and discoveries, we propose a simple yet effective approach, HarmonyDream, which automatically adjusts loss coefficients to maintain task harmonization, i. e. a dynamic equilibrium between the two tasks in world model learning. Our experiments show that the base MBRL method equipped with HarmonyDream gains 10%-69% absolute performance boosts on visual robotic tasks and sets a new state-of-the-art result on the Atari 100K benchmark. Code is available at https: //github. com/thuml/HarmonyDream.

UAI Conference 2024 Conference Paper

Hybrid CtrlFormer: Learning Adaptive Search Space Partition for Hybrid Action Control via Transformer-based Monte Carlo Tree Search

  • Jiashun Liu
  • Xiaotian Hao
  • Jianye Hao
  • Yan Zheng 0002
  • Yujing Hu
  • Changjie Fan
  • Tangjie Lv
  • Zhipeng Hu

Hybrid action control tasks are common in the real world, which require controlling some discrete and continuous actions simultaneously. To solve these tasks, existing Deep Reinforcement learning (DRL) methods either directly build a separate policy for each type of action or simplify the hybrid action space into a discrete or continuous action control problem. However, these methods neglect the challenge of exploration resulting from the complexity of the hybrid action space. Thus, it is necessary to design more sample efficient algorithms. To this end, we propose a novel Hybrid Control Transformer (Hybrid CtrlFormer), to achieve better exploration and exploitation for the hybrid action control problems. The core idea is: 1) we construct a hybrid action space tree with the discrete actions at the higher level and the continuous parameter space at the lower level. Each parameter space is split into multiple subregions. 2) To simplify the exploration space, a Transformer-based Monte-Carlo tree search method is designed to efficiently evaluate and partition the hybrid action space into good and bad subregions along the tree. Our method achieves state-of-the-art performance and sample efficiency in a variety of environments with discrete-continuous action space.

ICML Conference 2024 Conference Paper

Improving Generalization in Offline Reinforcement Learning via Adversarial Data Splitting

  • Da Wang
  • Lin Li 0090
  • Wei Wei 0018
  • Qixian Yu
  • Jianye Hao
  • Jiye Liang

Offline Reinforcement Learning (RL) commonly suffers from the out-of-distribution (OOD) overestimation issue due to the distribution shift. Prior work gradually shifts their focus from suppressing OOD overestimation to avoiding overly conservative learning from suboptimal behavior policies to improve generalization. However, most approaches explicitly delimit boundaries for OOD actions based on the support in the dataset, which can potentially impede the data near these boundaries from acquiring realistic estimates. This paper investigates how to loosen the rigid demarcation of OOD boundaries, adaptively extracting knowledge from empirical data to implicitly improve the model’s generalization to nearby unseen data. We introduce an adversarial data splitting (ADS) framework that enforces the model to generalize the distribution shifts simulated from the train/validation subsets splitting of the dataset. Specifically, ADS is modeled as a min-max optimization problem inspired by meta-learning and solved by iterating over the following two steps. First, we train the model on the train-subset to minimize its loss on the validation-subset. Then, we adversarially generate the "hardest" train/validation subsets with the maximum distribution shift, making the model incapable of generalization at that splitting. We derive a generalization error bound for theoretically understanding ADS and verify the effectiveness with extensive experiments. Code is available at https: //github. com/DkING-lv6/ADS.

NeurIPS Conference 2024 Conference Paper

Iteratively Refined Behavior Regularization for Offline Reinforcement Learning

  • Yi Ma
  • Jianye Hao
  • Xiaohan Hu
  • Yan Zheng
  • Chenjun Xiao

One of the fundamental challenges for offline reinforcement learning (RL) is ensuring robustness to data distribution. Whether the data originates from a near-optimal policy or not, we anticipate that an algorithm should demonstrate its ability to learn an effective control policy that seamlessly aligns with the inherent distribution of offline data. Unfortunately, behavior regularization, a simple yet effective offline RL algorithm, tends to struggle in this regard. In this paper, we propose a new algorithm that substantially enhances behavior-regularization based on conservative policy iteration. Our key observation is that by iteratively refining the reference policy used for behavior regularization, conservative policy update guarantees gradually improvement, while also implicitly avoiding querying out-of-sample actions to prevent catastrophic learning failures. We prove that in the tabular setting this algorithm is capable of learning the optimal policy covered by the offline dataset, commonly referred to as the in-sample optimal policy. We then explore several implementation details of the algorithm when function approximations are applied. The resulting algorithm is easy to implement, requiring only a few lines of code modification to existing methods. Experimental results on the D4RL benchmark indicate that our method outperforms previous state-of-the-art baselines in most tasks, clearly demonstrate its superiority over behavior regularization.

NeurIPS Conference 2024 Conference Paper

iVideoGPT: Interactive VideoGPTs are Scalable World Models

  • Jialong Wu
  • Shaofeng Yin
  • Ningya Feng
  • Xu He
  • Dong Li
  • Jianye Hao
  • Mingsheng Long

World models empower model-based agents to interactively explore, reason, and plan within imagined environments for real-world decision-making. However, the high demand for interactivity poses challenges in harnessing recent advancements in video generative models for developing world models at scale. This work introduces Interactive VideoGPT (iVideoGPT), a scalable autoregressive transformer framework that integrates multimodal signals—visual observations, actions, and rewards—into a sequence of tokens, facilitating an interactive experience of agents via next-token prediction. iVideoGPT features a novel compressive tokenization technique that efficiently discretizes high-dimensional visual observations. Leveraging its scalable architecture, we are able to pre-train iVideoGPT on millions of human and robotic manipulation trajectories, establishing a versatile foundation that is adaptable to serve as interactive world models for a wide range of downstream tasks. These include action-conditioned video prediction, visual planning, and model-based reinforcement learning, where iVideoGPT achieves competitive performance compared with state-of-the-art methods. Our work advances the development of interactive general world models, bridging the gap between generative video models and practical model-based reinforcement learning applications. Code and pre-trained models are available at https: //thuml. github. io/iVideoGPT.

ICML Conference 2024 Conference Paper

KISA: A Unified Keyframe Identifier and Skill Annotator for Long-Horizon Robotics Demonstrations

  • Longxin Kou
  • Fei Ni 0001
  • Yan Zheng 0002
  • Jinyi Liu 0002
  • Yifu Yuan
  • Zibin Dong
  • Jianye Hao

Robotic manipulation tasks often span over long horizons and encapsulate multiple subtasks with different skills. Learning policies directly from long-horizon demonstrations is challenging without intermediate keyframes guidance and corresponding skill annotations. Existing approaches for keyframe identification often struggle to offer reliable decomposition for low accuracy and fail to provide semantic relevance between keyframes and skills. For this, we propose a unified K eyframe I dentifier and S kill A notator ( KISA ) that utilizes pretrained visual-language representations for precise and interpretable decomposition of unlabeled demonstrations. Specifically, we develop a simple yet effective temporal enhancement module that enriches frame-level representations with expanded receptive fields to capture semantic dynamics at the video level. We further propose coarse contrastive learning and fine-grained monotonic encouragement to enhance the alignment between visual representations from keyframes and language representations from skills. The experimental results across three benchmarks demonstrate that KISA outperforms competitive baselines in terms of accuracy and interpretability of keyframe identification. Moreover, KISA exhibits robust generalization capabilities and the flexibility to incorporate various pretrained representations.

AAAI Conference 2024 Conference Paper

Multiagent Gumbel MuZero: Efficient Planning in Combinatorial Action Spaces

  • Xiaotian Hao
  • Jianye Hao
  • Chenjun Xiao
  • Kai Li
  • Dong Li
  • Yan Zheng

AlphaZero and MuZero have achieved state-of-the-art (SOTA) performance in a wide range of domains, including board games and robotics, with discrete and continuous action spaces. However, to obtain an improved policy, they often require an excessively large number of simulations, especially for domains with large action spaces. As the simulation budget decreases, their performance drops significantly. In addition, many important real-world applications have combinatorial (or exponential) action spaces, making it infeasible to search directly over all possible actions. In this paper, we extend AlphaZero and MuZero to learn and plan in more complex multiagent (MA) Markov decision processes, where the action spaces increase exponentially with the number of agents. Our new algorithms, MA Gumbel AlphaZero and MA Gumbel MuZero, respectively without and with model learning, achieve superior performance on cooperative multiagent control problems, while reducing the number of environmental interactions by up to an order of magnitude compared to model-free approaches. In particular, we significantly improve prior performance when planning with much fewer simulation budgets. The code and appendix are available at https://github.com/tjuHaoXiaotian/MA-MuZero.

AAAI Conference 2024 Conference Paper

OVD-Explorer: Optimism Should Not Be the Sole Pursuit of Exploration in Noisy Environments

  • Jinyi Liu
  • Zhi Wang
  • Yan Zheng
  • Jianye Hao
  • Chenjia Bai
  • Junjie Ye
  • Zhen Wang
  • Haiyin Piao

In reinforcement learning, the optimism in the face of uncertainty (OFU) is a mainstream principle for directing exploration towards less explored areas, characterized by higher uncertainty. However, in the presence of environmental stochasticity (noise), purely optimistic exploration may lead to excessive probing of high-noise areas, consequently impeding exploration efficiency. Hence, in exploring noisy environments, while optimism-driven exploration serves as a foundation, prudent attention to alleviating unnecessary over-exploration in high-noise areas becomes beneficial. In this work, we propose Optimistic Value Distribution Explorer (OVD-Explorer) to achieve a noise-aware optimistic exploration for continuous control. OVD-Explorer proposes a new measurement of the policy's exploration ability considering noise in optimistic perspectives, and leverages gradient ascent to drive exploration. Practically, OVD-Explorer can be easily integrated with continuous control RL algorithms. Extensive evaluations on the MuJoCo and GridChaos tasks demonstrate the superiority of OVD-Explorer in achieving noise-aware optimistic exploration.

AAMAS Conference 2024 Conference Paper

PADDLE: Logic Program Guided Policy Reuse in Deep Reinforcement Learning

  • Hao Zhang
  • Tianpei Yang
  • Yan Zheng
  • Jianye Hao
  • Matthew E. Taylor

Learning new skills through previous experience is regular in human life, which is the core idea of Transfer Reinforcement Learning (TRL). TRL requires the agent to learn when and which source policy is the best to reuse as the target task’s policy and how to reuse the source policy. Most TRL methods learn, transfer, and reuse blackbox policies, which is hard to explain: 1) when to reuse, 2) which source policy is effective, and reduces transfer efficiency. In this paper, we propose a novel TRL method called ProgrAm guiDeD poLicy rEuse (PADDLE). PADDLE can measure the logic similarities between tasks and transfer knowledge which reflects the logic behind the target task. To achieve this, we propose a hybrid decision model that synthesizes high-level logic programs and learns low-level DRL policy to learn source tasks. Second, we propose a transferability metric that can measure the logic similarity between the target task and source tasks. Last, we combine it with the lowlevel policy similarity to select the appropriate source policy as the guiding policy for the target task. Experimental results show that PADDLE can effectively select the appropriate source tasks to guide learning on the target task, outperforming black-box TRL methods.

NeurIPS Conference 2024 Conference Paper

PERIA: Perceive, Reason, Imagine, Act via Holistic Language and Vision Planning for Manipulation

  • Fei Ni
  • Jianye Hao
  • Shiguang Wu
  • Longxin Kou
  • Yifu Yuan
  • Zibin Dong
  • Jinyi Liu
  • Mingzhi Li

Long-horizon manipulation tasks with general instructions often implicitly encapsulate multiple sub-tasks, posing significant challenges in instruction following. While language planning is a common approach to decompose general instructions into stepwise sub-instructions, text-only guidance may lack expressiveness and lead to potential ambiguity. Considering that humans often imagine and visualize sub-instructions reasoning out before acting, the imagined subgoal images can provide more intuitive guidance and enhance the reliability of decomposition. Inspired by this, we propose PERIA ( PE rceive, R eason, I magine, A ct), a novel framework that integrates holistic language planning and vision planning for long-horizon manipulation tasks with complex instructions, leveraging both logical and intuitive aspects of task decomposition. Specifically, we first perform a lightweight multimodal alignment on the encoding side to empower the MLLM to perceive visual details and language instructions. The MLLM is then jointly instruction-tuned with a pretrained image-editing model to unlock capabilities of simultaneous reasoning of language instructions and generation of imagined subgoals. Furthermore, we introduce a consistency alignment loss to encourage coherent subgoal images and align with their corresponding instructions, mitigating potential hallucinations and semantic conflicts between the two planning manners. Comprehensive evaluations across three task domains demonstrate that PERIA, benefiting from holistic language and vision planning, significantly outperforms competitive baselines in both instruction following accuracy and task success rate on complex manipulation tasks.

AIJ Journal 2024 Journal Article

Pessimistic value iteration for multi-task data sharing in Offline Reinforcement Learning

  • Chenjia Bai
  • Lingxiao Wang
  • Jianye Hao
  • Zhuoran Yang
  • Bin Zhao
  • Zhen Wang
  • Xuelong Li

Offline Reinforcement Learning (RL) has shown promising results in learning a task-specific policy from a fixed dataset. However, successful offline RL often relies heavily on the coverage and quality of the given dataset. In scenarios where the dataset for a specific task is limited, a natural approach is to improve offline RL with datasets from other tasks, namely, to conduct Multi-Task Data Sharing (MTDS). Nevertheless, directly sharing datasets from other tasks exacerbates the distribution shift in offline RL. In this paper, we propose an uncertainty-based MTDS approach that shares the entire dataset without data selection. Given ensemble-based uncertainty quantification, we perform pessimistic value iteration on the shared offline dataset, which provides a unified framework for single- and multi-task offline RL. We further provide theoretical analysis, which shows that the optimality gap of our method is only related to the expected data coverage of the shared dataset, thus resolving the distribution shift issue in data sharing. Empirically, we release an MTDS benchmark and collect datasets from three challenging domains. The experimental results show our algorithm outperforms the previous state-of-the-art methods in challenging MTDS problems.

AAAI Conference 2024 Conference Paper

PORTAL: Automatic Curricula Generation for Multiagent Reinforcement Learning

  • Jizhou Wu
  • Jianye Hao
  • Tianpei Yang
  • Xiaotian Hao
  • Yan Zheng
  • Weixun Wang
  • Matthew E. Taylor

Despite many breakthroughs in recent years, it is still hard for MultiAgent Reinforcement Learning (MARL) algorithms to directly solve complex tasks in MultiAgent Systems (MASs) from scratch. In this work, we study how to use Automatic Curriculum Learning (ACL) to reduce the number of environmental interactions required to learn a good policy. In order to solve a difficult task, ACL methods automatically select a sequence of tasks (i.e., curricula). The idea is to obtain maximum learning progress towards the final task by continuously learning on tasks that match the current capabilities of the learners. The key question is how to measure the learning progress of the learner for better curriculum selection. We propose a novel ACL framework, PrOgRessive mulTiagent Automatic curricuLum (PORTAL), for MASs. PORTAL selects curricula according to two critera: 1) How difficult is a task, relative to the learners’ current abilities? 2) How similar is a task, relative to the final task? By learning a shared feature space between tasks, PORTAL is able to characterize different tasks based on the distribution of features and select those that are similar to the final task. Also, the shared feature space can effectively facilitate the policy transfer between curricula. Experimental results show that PORTAL can train agents to master extremely hard cooperative tasks, which can not be achieved with previous state-of-the-art MARL algorithms.

AAAI Conference 2024 Conference Paper

PreRoutGNN for Timing Prediction with Order Preserving Partition: Global Circuit Pre-training, Local Delay Learning and Attentional Cell Modeling

  • Ruizhe Zhong
  • Junjie Ye
  • Zhentao Tang
  • Shixiong Kai
  • Mingxuan Yuan
  • Jianye Hao
  • Junchi Yan

Pre-routing timing prediction has been recently studied for evaluating the quality of a candidate cell placement in chip design. It involves directly estimating the timing metrics for both pin-level (slack, slew) and edge-level (net delay, cell delay), without time-consuming routing. However, it often suffers from signal decay and error accumulation due to the long timing paths in large-scale industrial circuits. To address these challenges, we propose a two-stage approach. First, we propose global circuit training to pre-train a graph auto-encoder that learns the global graph embedding from circuit netlist. Second, we use a novel node updating scheme for message passing on GCN, following the topological sorting sequence of the learned graph embedding and circuit graph. This scheme residually models the local time delay between two adjacent pins in the updating sequence, and extracts the lookup table information inside each cell via a new attention mechanism. To handle large-scale circuits efficiently, we introduce an order preserving partition scheme that reduces memory consumption while maintaining the topological dependencies. Experiments on 21 real world circuits achieve a new SOTA R2 of 0.93 for slack prediction, which is significantly surpasses 0.59 by previous SOTA method. Code will be available at: https://github.com/Thinklab-SJTU/EDA-AI.

ICML Conference 2024 Conference Paper

Reinforcement Learning within Tree Search for Fast Macro Placement

  • Zijie Geng
  • Jie Wang 0005
  • Ziyan Liu
  • Siyuan Xu
  • Zhentao Tang
  • Mingxuan Yuan
  • Jianye Hao
  • Yongdong Zhang 0001

Macro placement is a crucial step in modern chip design, and reinforcement learning (RL) has recently emerged as a promising technique for improving the placement quality. However, existing RL-based techniques are hindered by their low sample efficiency, requiring numerous online rollouts or substantial offline expert data to achieve bootstrap, which are often impractical in industrial scenarios. To address this challenge, we propose a novel sample-efficient framework, namely EfficientPlace, for fast macro placement. EfficientPlace integrates a global tree search algorithm to strategically direct the optimization process, as well as a RL agent for local policy learning to advance the tree search. Experiments on commonly used benchmarks demonstrate that EfficientPlace achieves remarkable placement quality within a short timeframe, outperforming recent state-of-the-art approaches.

ICLR Conference 2024 Conference Paper

Rethinking Branching on Exact Combinatorial Optimization Solver: The First Deep Symbolic Discovery Framework

  • Yufei Kuang
  • Jie Wang 0005
  • Haoyang Liu 0002
  • Fangzhou Zhu
  • Xijun Li
  • Jia Zeng
  • Jianye Hao
  • Bin Li 0025

Machine learning (ML) has been shown to successfully accelerate solving NP-hard combinatorial optimization (CO) problems under the branch and bound framework. However, the high training and inference cost and limited interpretability of ML approaches severely limit their wide application to modern exact CO solvers. In contrast, human-designed policies---though widely integrated in modern CO solvers due to their compactness and reliability---can not capture data-driven patterns for higher performance. To combine the advantages of the two paradigms, we propose the first symbolic discovery framework---namely, deep symbolic discovery for exact combinatorial optimization solver (Symb4CO)---to learn high-performance symbolic policies on the branching task. Specifically, we show the potential existence of small symbolic policies empirically, employ a large neural network to search in the high-dimensional discrete space, and compile the learned symbolic policies directly for fast deployment. Experiments show that the Symb4CO learned purely CPU-based policies consistently achieve *comparable* performance to previous GPU-based state-of-the-art approaches. Furthermore, the appealing features of Symb4CO include its high training (*ten training instances*) and inference (*one CPU core*) efficiency and good interpretability (*one-line expressions*), making it simple and reliable for deployment. The results show encouraging potential for the *wide* deployment of ML to modern CO solvers.

ICML Conference 2024 Conference Paper

Rethinking Decision Transformer via Hierarchical Reinforcement Learning

  • Yi Ma 0005
  • Jianye Hao
  • Hebin Liang
  • Chenjun Xiao

Decision Transformer (DT) is an innovative algorithm leveraging recent advances of the transformer architecture in reinforcement learning (RL). However, a notable limitation of DT is its reliance on recalling trajectories from datasets, losing the capability to seamlessly stitch sub-optimal trajectories together. In this work we introduce a general sequence modeling framework for studying sequential decision making through the lens of Hierarchical RL. At the time of making decisions, a high-level policy first proposes an ideal prompt for the current state, a low-level policy subsequently generates an action conditioned on the given prompt. We show DT emerges as a special case of this framework with certain choices of high-level and low-level policies, and discuss the potential failure of these choices. Inspired by these observations, we study how to jointly optimize the high-level and low-level policies to enable the stitching ability, which further leads to the development of new offline RL algorithms. Our empirical results clearly show that the proposed algorithms significantly surpass DT on several control and navigation benchmarks. We hope our contributions can inspire the integration of transformer architectures within the field of RL.

ICRA Conference 2024 Conference Paper

Safe Table Tennis Swing Stroke with Low-Cost Hardware

  • Francesco Cursi
  • Marcus Kalander
  • Shuang Wu 0005
  • Xidi Xue
  • Yu Tian
  • Guangjian Tian
  • Xingyue Quan
  • Jianye Hao

Playing table tennis with a human player is a challenging robotic task due to its dynamic nature. Despite a number of researches being devoted to developing robotic table tennis systems, most of the works have demanding hardware requirements and ignore safety measures when generating the swing stoke. To address these issues, we propose a safe motion planning framework that fully pushes the robotic hardware performance limits to play table tennis. In particular, we propose a pipeline to generate manipulator joint trajectories with environmental safety constraints and scale the trajectories to satisfy joint movement limitations. We use three different agents to validate the planning algorithm with our handmade robot platform in both simulation and real-world environments.

ICML Conference 2024 Conference Paper

Sample-Efficient Multiagent Reinforcement Learning with Reset Replay

  • Yaodong Yang 0002
  • Guangyong Chen
  • Jianye Hao
  • Pheng-Ann Heng

The popularity of multiagent reinforcement learning (MARL) is growing rapidly with the demand for real-world tasks that require swarm intelligence. However, a noticeable drawback of MARL is its low sample efficiency, which leads to a huge amount of interactions with the environment. Surprisingly, few MARL works focus on this practical problem especially in the parallel environment setting, which greatly hampers the application of MARL into the real world. In response to this gap, in this paper, we propose Multiagent Reinforcement Learning with Reset Replay (MARR) to greatly improve the sample efficiency of MARL by enabling MARL training at a high replay ratio in the parallel environment setting for the first time. To achieve this, first, a reset strategy is introduced for maintaining the network plasticity to ensure that MARL continually learns with a high replay ratio. Second, MARR incorporates a data augmentation technique to boost the sample efficiency further. Extensive experiments in SMAC and MPE show that MARR significantly improves the performance of various MARL approaches with much fewer environment interactions.

ICLR Conference 2024 Conference Paper

Sample-Efficient Quality-Diversity by Cooperative Coevolution

  • Ke Xue 0001
  • Ren-Jian Wang
  • Pengyi Li 0001
  • Dong Li 0016
  • Jianye Hao
  • Chao Qian 0001

Quality-Diversity (QD) algorithms, as a subset of evolutionary algorithms, have emerged as a powerful optimization paradigm with the aim of generating a set of high-quality and diverse solutions. Although QD has demonstrated competitive performance in reinforcement learning, its low sample efficiency remains a significant impediment for real-world applications. Recent research has primarily focused on augmenting sample efficiency by refining selection and variation operators of QD. However, one of the less considered yet crucial factors is the inherently large-scale issue of the QD optimization problem. In this paper, we propose a novel Cooperative Coevolution QD (CCQD) framework, which decomposes a policy network naturally into two types of layers, corresponding to representation and decision respectively, and thus simplifies the problem significantly. The resulting two (representation and decision) subpopulations are coevolved cooperatively. CCQD can be implemented with different selection and variation operators. Experiments on several popular tasks within the QDAX suite demonstrate that an instantiation of CCQD achieves approximately a 200% improvement in sample efficiency.

NeurIPS Conference 2024 Conference Paper

The Ladder in Chaos: Improving Policy Learning by Harnessing the Parameter Evolving Path in A Low-dimensional Space

  • Hongyao Tang
  • Min Zhang
  • Chen Chen
  • Jianye Hao

Knowing the learning dynamics of policy is significant to unveiling the mysteries of Reinforcement Learning (RL). It is especially crucial yet challenging to Deep RL, from which the remedies to notorious issues like sample inefficiency and learning instability could be obtained. In this paper, we study how the policy networks of typical DRL agents evolve during the learning process by empirically investigating several kinds of temporal change for each policy parameter. In popular MuJoCo and DeepMind Control Suite (DMC) environments, we find common phenomena for TD3 and RAD agents: (1) the activity of policy network parameters is highly asymmetric and policy networks advance monotonically along a very limited number of major parameter directions; (2) severe detours occur in parameter update and harmonic-like changes are observed for all minor parameter directions. By performing a novel temporal SVD along the policy learning path, the major and minor parameter directions are identified as the columns of the right unitary matrix associated with dominant and insignificant singular values respectively. Driven by the discoveries above, we propose a simple and effective method, called Policy Path Trimming and Boosting (PPTB), as a general plug-in improvement to DRL algorithms. The key idea of PPTB is to trim the policy learning path by canceling the policy updates in minor parameter directions, and boost the learning path by encouraging the advance in major directions. In experiments, we demonstrate that our method improves the learning performance of TD3, RAD, and DoubleDQN regarding scores and efficiency in MuJoCo, DMC, and MinAtar tasks respectively.

ICML Conference 2024 Conference Paper

Towards General Algorithm Discovery for Combinatorial Optimization: Learning Symbolic Branching Policy from Bipartite Graph

  • Yufei Kuang
  • Jie Wang 0005
  • Yuyan Zhou
  • Xijun Li
  • Fangzhou Zhu
  • Jianye Hao
  • Feng Wu 0001

Machine learning (ML) approaches have been successfully applied to accelerating exact combinatorial optimization (CO) solvers. However, many of them fail to explain what patterns they have learned that accelerate the CO algorithms due to the black-box nature of ML models like neural networks, and thus they prevent researchers from further understanding the tasks they are interested in. To tackle this problem, we propose the first graph-based algorithm discovery framework—namely, graph symbolic discovery for exact combinatorial optimization solver (GS4CO)—that learns interpretable branching policies directly from the general bipartite graph representation of CO problems. Specifically, we design a unified representation for symbolic policies with graph inputs, and then we employ a Transformer with multiple tree-structural encodings to generate symbolic trees end-to-end, which effectively reduces the cumulative error from iteratively distilling graph neural networks. Experiments show that GS4CO learned interpretable and lightweight policies outperform all the baselines on CPU machines, including both the human-designed and the learning-based. GS4CO shows an encouraging step towards general algorithm discovery on modern CO solvers.

NeurIPS Conference 2024 Conference Paper

Towards Next-Generation Logic Synthesis: A Scalable Neural Circuit Generation Framework

  • Zhihai Wang
  • Jie Wang
  • Qingyue Yang
  • Yinqi Bai
  • Xing Li
  • Lei Chen
  • Jianye Hao
  • Mingxuan Yuan

Logic Synthesis (LS) aims to generate an optimized logic circuit satisfying a given functionality, which generally consists of circuit translation and optimization. It is a challenging and fundamental combinatorial optimization problem in integrated circuit design. Traditional LS approaches rely on manually designed heuristics to tackle the LS task, while machine learning recently offers a promising approach towards next-generation logic synthesis by neural circuit generation and optimization. In this paper, we first revisit the application of differentiable neural architecture search (DNAS) methods to circuit generation and found from extensive experiments that existing DNAS methods struggle to exactly generate circuits, scale poorly to large circuits, and exhibit high sensitivity to hyper-parameters. Then we provide three major insights for these challenges from extensive empirical analysis: 1) DNAS tends to overfit to too many skip-connections, consequently wasting a significant portion of the network's expressive capabilities; 2) DNAS suffers from the structure bias between the network architecture and the circuit inherent structure, leading to inefficient search; 3) the learning difficulty of different input-output examples varies significantly, leading to severely imbalanced learning. To address these challenges in a systematic way, we propose a novel regularized triangle-shaped circuit network generation framework, which leverages our key insights for completely accurate and scalable circuit generation. Furthermore, we propose an evolutionary algorithm assisted by reinforcement learning agent restarting technique for efficient and effective neural circuit optimization. Extensive experiments on four different circuit benchmarks demonstrate that our method can precisely generate circuits with up to 1200 nodes. Moreover, our synthesized circuits significantly outperform the state-of-the-art results from several competitive winners in IWLS 2022 and 2023 competitions.

ICLR Conference 2024 Conference Paper

Uni-RLHF: Universal Platform and Benchmark Suite for Reinforcement Learning with Diverse Human Feedback

  • Yifu Yuan
  • Jianye Hao
  • Yi Ma 0005
  • Zibin Dong
  • Hebin Liang
  • Jinyi Liu 0002
  • Zhixin Feng
  • Kai Zhao

Reinforcement Learning with Human Feedback (RLHF) has received significant attention for performing tasks without the need for costly manual reward design by aligning human preferences. It is crucial to consider diverse human feedback types and various learning methods in different environments. However, quantifying progress in RLHF with diverse feedback is challenging due to the lack of standardized annotation platforms and widely used unified benchmarks. To bridge this gap, we introduce **Uni-RLHF**, a comprehensive system implementation tailored for RLHF. It aims to provide a complete workflow from *real human feedback*, fostering progress in the development of practical problems. Uni-RLHF contains three packages: 1) a universal multi-feedback annotation platform, 2) large-scale crowdsourced feedback datasets, and 3) modular offline RLHF baseline implementations. Uni-RLHF develops a user-friendly annotation interface tailored to various feedback types, compatible with a wide range of mainstream RL environments. We then establish a systematic pipeline of crowdsourced annotations, resulting in large-scale annotated datasets comprising more than 15 million steps across 30 popular tasks. Through extensive experiments, the results in the collected datasets demonstrate competitive performance compared to those from well-designed manual rewards. We evaluate various design choices and offer insights into their strengths and potential areas of improvement. We wish to build valuable open-source platforms, datasets, and baselines to facilitate the development of more robust and reliable RLHF solutions based on realistic human feedback. The website is available at https://uni-rlhf.github.io/.

ICML Conference 2024 Conference Paper

Unlock the Cognitive Generalization of Deep Reinforcement Learning via Granular Ball Representation

  • Jiashun Liu
  • Jianye Hao
  • Yi Ma 0005
  • Shuyin Xia

The policies learned by humans in simple scenarios can be deployed in complex scenarios with the same task logic through limited feature alignment training, a process referred to as cognitive generalization or systematic generalization. Thus, a plausible conjecture is that unlocking cognitive generalization in DRL could enable effective generalization of policies from simple to complex scenarios through reward-agnostic fine-tuning. This would eliminate the need for designing reward functions in complex scenarios, thus reducing environment-building costs. In this paper, we propose a general framework to enhance the cognitive generalization ability of standard DRL methods. Our framework builds a cognitive latent space in a simple scenario, then segments the latent space to cluster samples with similar environmental influences into same subregion. During the fine-tuning in the complex scenario, the policy uses cognitive latent space to align the new sample with the same subregion sample collected from the simple scenario and approximates the rewards and Q values of the new samples for policy update. Based on this framework, we propose Granular Ball Reinforcement Leaning (GBRL), a practical algorithm via Variational Autoencoder (VAE) and Granular Ball Representation. GBRL achieves effective policy generalization on various difficult scenarios with the same task logic.

NeurIPS Conference 2024 Conference Paper

Unlock the Intermittent Control Ability of Model Free Reinforcement Learning

  • Jiashun Liu
  • Jianye Hao
  • Xiaotian Hao
  • Yi Ma
  • Yan Zheng
  • Yujing Hu
  • Tangji Lv

Intermittent control problems are common in real world. The interactions between the decision maker and the executor can be discontinuous (intermittent) due to various types of interruptions, e. g. unstable communication channel. Due to intermittent interaction, agents are unable to acquire the state sent by the executor and cannot transmit actions to the executor within a period of time step, i. e. bidirectional blockage, which may lead to inefficiencies of reinforcement learning policies and prevent the executors from completing the task. Such problem is not well studied in the RL community. In this paper, we model Intermittent control problem as an Intermittent Control Markov Decision Process, i. e agents are expected to generate action sequences corresponding to the unavailable states and transmit them before disabling interactions to ensure the smooth and effective motion of executors. However, directly generating multiple future actions in the original action space has unnatural motion issue and exploration difficulty. We propose M ulti-step A ction R epre S entation ( MARS ), which encodes a sequence of actions from the original action space to a compact and decodable latent space. Then based on the latent action sequence representation, the mainstream RL methods can be easily optimized to learn a smooth and efficient motion policy. Extensive experiments on simulation tasks and real-world robotic grasping tasks show that MARS significantly improves the learning efficiency and final performances compared with existing baselines.

ICML Conference 2024 Conference Paper

Value-Evolutionary-Based Reinforcement Learning

  • Pengyi Li 0001
  • Jianye Hao
  • Hongyao Tang
  • Yan Zheng 0002
  • Fazl Barez

Combining Evolutionary Algorithms (EAs) and Reinforcement Learning (RL) for policy search has been proven to improve RL performance. However, previous works largely overlook value-based RL in favor of merging EAs with policy-based RL. This paper introduces Value-Evolutionary-Based Reinforcement Learning (VEB-RL) that focuses on the integration of EAs with value-based RL. The framework maintains a population of value functions instead of policies and leverages negative Temporal Difference error as the fitness metric for evolution. The metric is more sample-efficient for population evaluation than cumulative rewards and is closely associated with the accuracy of the value function approximation. Additionally, VEB-RL enables elites of the population to interact with the environment to offer high-quality samples for RL optimization, whereas the RL value function participates in the population’s evolution in each generation. Experiments on MinAtar and Atari demonstrate the superiority of VEB-RL in significantly improving DQN, Rainbow, and SPR. Our code is available on https: //github. com/yeshenpy/VEB-RL.

IJCAI Conference 2024 Conference Paper

vMFER: Von Mises-Fisher Experience Resampling Based on Uncertainty of Gradient Directions for Policy Improvement

  • Yiwen Zhu
  • Jinyi Liu
  • Wenya Wei
  • Qianyi Fu
  • Yujing Hu
  • Zhou Fang
  • Bo An
  • Jianye Hao

Reinforcement Learning (RL) is a widely employed technique in decision-making problems, encompassing two fundamental operations -- policy evaluation and policy improvement. Enhancing learning efficiency remains a key challenge in RL, with many efforts focused on using ensemble critics to boost policy evaluation efficiency. However, when using multiple critics, the actor in the policy improvement process can obtain different gradients. Previous studies have combined these gradients without considering their disagreements. Therefore, optimizing the policy improvement process is crucial to enhance learning efficiency. This study focuses on investigating the impact of gradient disagreements caused by ensemble critics on policy improvement. We introduce the concept of uncertainty of gradient directions as a means to measure the disagreement among gradients utilized in the policy improvement process. Through measuring the disagreement among gradients, we find that transitions with lower uncertainty of gradient directions are more reliable in the policy improvement process. Building on this analysis, we propose a method called von Mises-Fisher Experience Resampling (vMFER), which optimizes the policy improvement process by resampling transitions and assigning higher confidence to transitions with lower uncertainty of gradient directions. Our experiments demonstrate that vMFER significantly outperforms the benchmark and is particularly well-suited for ensemble structures in RL.

AAMAS Conference 2024 Conference Paper

vMFER: von Mises-Fisher Experience Resampling Based on Uncertainty of Gradient Directions for Policy Improvement of Actor-Critic Algorithms

  • Yiwen Zhu
  • Jinyi Liu
  • Wenya Wei
  • Qianyi Fu
  • Yujing Hu
  • Zhou Fang
  • Bo An
  • Jianye Hao

Reinforcement Learning (RL) is a widely employed technique in decision-making problems, encompassing two fundamental operations – policy evaluation and policy improvement. Actor-critic algorithms dominate the field of RL, but there is a challenge in improving their learning efficiency. To address this, ensemble critics are often employed to enhance policy evaluation efficiency. However, when using multiple critics, the actor in the policy improvement process can obtain different gradients. Previous studies have combined these gradients without considering their disagreements. Therefore, optimizing the policy improvement process is crucial to enhance the learning efficiency of actor-critic algorithms. This study focuses on investigating the impact of gradient disagreements caused by ensemble critics on policy improvement. We introduce the concept of uncertainty of gradient directions as a means to measure the disagreement among gradients utilized in the policy improvement process. Through measuring the disagreement among gradients, we find that transitions with lower uncertainty of gradient directions are more reliable in the policy improvement process. Building on this analysis, we propose a method called von Mises-Fisher Experience Resampling (vMFER), which optimizes This work is licensed under a Creative Commons Attribution International 4. 0 License. Proc. of the 23rd International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2024), N. Alechina, V. Dignum, M. Dastani, J. S. Sichman (eds.), May 6 – 10, 2024, Auckland, New Zealand. © 2024 International Foundation for Autonomous Agents and Multiagent Systems (www. ifaamas. org). the policy improvement process by resampling transitions and assigning higher confidence to transitions with lower uncertainty of gradient directions. Our experiments on Mujoco robotic control tasks and robotic arm tasks with sparse rewards demonstrate that vMFER significantly outperforms the benchmark and is particularly well-suited for ensemble structures in RL.

JAAMAS Journal 2023 Journal Article

Accelerating deep reinforcement learning via knowledge-guided policy network

  • Yuanqiang Yu
  • Peng Zhang
  • Jianye Hao

Abstract Deep reinforcement learning has contributed to dramatic advances in many tasks, such as playing games, controlling robots, and navigating complex environments. However, it requires many interactions with the environment. This is different from the human learning process since humans can use prior knowledge, which can significantly speed up the learning process as it avoids unnecessary exploration. Previous works integrating knowledge in RL did not model uncertainty in human cognition, which reduces the reliability of knowledge. In this paper, we propose a knowledge-guided policy network, a novel framework that combines suboptimal human knowledge with reinforcement learning. Our framework consists of a fuzzy rule controller representing human knowledge and a refined module to fine-tune suboptimal prior knowledge. The proposed framework is end-to-end and can be combined with existing reinforcement learning algorithms such as PPO, AC, and SAC. We conduct experiments on both discrete and continuous control tasks. The empirical results show that our approach, which combines suboptimal human knowledge and RL, significantly improves the learning efficiency of basic RL algorithms, even with very low-performance human prior knowledge. Additional experiments are conducted on the number of fuzzy rules and the interpretability of the policy, which make our proposed framework more complete and reasonable. The code for this research is released under the project page of https: //github. com/yuyuanq/reinforcement-learning-using-knowledge-controller.

ECAI Conference 2023 Conference Paper

BiERL: A Meta Evolutionary Reinforcement Learning Framework via Bilevel Optimization

  • Junyi Wang
  • Yuanyang Zhu
  • Zhi Wang 0001
  • Yan Zheng 0002
  • Jianye Hao
  • Chunlin Chen 0001

Evolutionary reinforcement learning (ERL) algorithms recently raise attention in tackling complex reinforcement learning (RL) problems due to high parallelism, while they are prone to insufficient exploration or model collapse without carefully tuning hyperparameters (aka meta-parameters). In the paper, we propose a general meta ERL framework via bilevel optimization (BiERL) to jointly update hyperparameters in parallel to training the ERL model within a single agent, which relieves the need for prior domain knowledge or costly optimization procedure before model deployment. We design an elegant meta-level architecture that embeds the inner-level’s evolving experience into an informative population representation and introduce a simple and feasible evaluation of the meta-level fitness function to facilitate learning efficiency. We perform extensive experiments in MuJoCo and Box2D tasks to verify that as a general framework, BiERL outperforms various baselines and consistently improves the learning performance for a diversity of ERL algorithms.

ICLR Conference 2023 Conference Paper

Boosting Multiagent Reinforcement Learning via Permutation Invariant and Permutation Equivariant Networks

  • Jianye Hao
  • Xiaotian Hao
  • Hangyu Mao
  • Weixun Wang
  • Yaodong Yang 0002
  • Dong Li 0016
  • Yan Zheng 0002
  • Zhen Wang 0004

The state space in Multiagent Reinforcement Learning (MARL) grows exponentially with the agent number. Such a curse of dimensionality results in poor scalability and low sample efficiency, inhibiting MARL for decades. To break this curse, we propose a unified agent permutation framework that exploits the permutation invariance (PI) and permutation equivariance (PE) inductive biases to reduce the multiagent state space. Our insight is that permuting the order of entities in the factored multiagent state space does not change the information. Specifically, we propose two novel implementations: a Dynamic Permutation Network (DPN) and a Hyper Policy Network (HPN). The core idea is to build separate entity-wise PI input and PE output network modules to connect the entity-factored state space and action space in an end-to-end way. DPN achieves such connections by two separate module selection networks, which consistently assign the same input module to the same input entity (guarantee PI) and assign the same output module to the same entity-related output (guarantee PE). To enhance the representation capability, HPN replaces the module selection networks of DPN with hypernetworks to directly generate the corresponding module weights. Extensive experiments in SMAC, Google Research Football and MPE validate that the proposed methods significantly boost the performance and the learning efficiency of existing MARL algorithms. Remarkably, in SMAC, we achieve 100% win rates in almost all hard and super-hard scenarios (never achieved before).

ICLR Conference 2023 Conference Paper

CFlowNets: Continuous Control with Generative Flow Networks

  • Yinchuan Li
  • Shuang Luo
  • Haozhi Wang
  • Jianye Hao

Generative flow networks (GFlowNets), as an emerging technique, can be used as an alternative to reinforcement learning for exploratory control tasks. GFlowNets aims to sample actions with a probability proportional to the reward, similar to sampling different candidates in an active learning fashion. However, existing GFlowNets cannot adapt to continuous control tasks because GFlowNets need to form a DAG and compute the flow matching loss by traversing the inflows and outflows of each node in the trajectory. In this paper, we propose generative continuous flow networks (CFlowNets) that can be applied to continuous control tasks. First, we present the theoretical formulation of CFlowNets. Then, a training framework for CFlowNets is proposed, including the action selection process, the flow approximation algorithm, and the continuous flow matching loss function. Afterward, we theoretically prove the error bound of the flow approximation. The error decreases rapidly as the number of flow samples increases. Finally, experimental results on continuous control tasks demonstrate the performance advantages of CFlowNets compared to many reinforcement learning methods, especially regarding exploration ability.

ICML Conference 2023 Conference Paper

ChiPFormer: Transferable Chip Placement via Offline Decision Transformer

  • Yao Lai
  • Jinxin Liu
  • Zhentao Tang
  • Bin Wang 0034
  • Jianye Hao
  • Ping Luo 0002

Placement is a critical step in modern chip design, aiming to determine the positions of circuit modules on the chip canvas. Recent works have shown that reinforcement learning (RL) can improve human performance in chip placement. However, such an RL-based approach suffers from long training time and low transfer ability in unseen chip circuits. To resolve these challenges, we cast the chip placement as an offline RL formulation and present ChiPFormer that enables learning a transferable placement policy from fixed offline data. ChiPFormer has several advantages that prior arts do not have. First, ChiPFormer can exploit offline placement designs to learn transferable policies more efficiently in a multi-task setting. Second, ChiPFormer can promote effective finetuning for unseen chip circuits, reducing the placement runtime from hours to minutes. Third, extensive experiments on 32 chip circuits demonstrate that ChiPFormer achieves significantly better placement quality while reducing the runtime by 10x compared to recent state-of-the-art approaches in both public benchmarks and realistic industrial tasks. The deliverables are released at https: //sites. google. com/view/chipformer/home.

ICLR Conference 2023 Conference Paper

DAG Matters! GFlowNets Enhanced Explainer for Graph Neural Networks

  • Wenqian Li
  • Yinchuan Li
  • Zhigang Li
  • Jianye Hao
  • Yan Pang

Uncovering rationales behind predictions of graph neural networks (GNNs) has received increasing attention over the years. Existing literature mainly focus on selecting a subgraph, through combinatorial optimization, to provide faithful explanations. However, the exponential size of candidate subgraphs limits the applicability of state-of-the-art methods to large-scale GNNs. We enhance on this through a different approach: by proposing a generative structure – GFlowNets-based GNN Explainer (GFlowExplainer), we turn the optimization problem into a step-by-step generative problem. Our GFlowExplainer aims to learn a policy that generates a distribution of subgraphs for which the probability of a subgraph is proportional to its’ reward. The proposed approach eliminates the influence of node sequence and thus does not need any pre-training strategies. We also propose a new cut vertex matrix to efficiently explore parent states for GFlowNets structure, thus making our approach applicable in a large-scale setting. We conduct extensive experiments on both synthetic and real datasets, and both qualitative and quantitative results show the superiority of our GFlowExplainer.

TMLR Journal 2023 Journal Article

Differentiable Logic Machines

  • Matthieu Zimmer
  • Xuening Feng
  • Claire Glanois
  • Zhaohui Jiang
  • Jianyi Zhang
  • Paul Weng
  • Dong Li
  • Jianye Hao

The integration of reasoning, learning, and decision-making is key to build more general artificial intelligence systems. As a step in this direction, we propose a novel neural-logic architecture, called differentiable logic machine (DLM), that can solve both inductive logic programming (ILP) and reinforcement learning (RL) problems, where the solution can be interpreted as a first-order logic program. Our proposition includes several innovations. Firstly, our architecture defines a restricted but expressive continuous relaxation of the space of first-order logic programs by assigning weights to predicates instead of rules, in contrast to most previous neural-logic approaches. Secondly, with this differentiable architecture, we propose several (supervised and RL) training procedures, based on gradient descent, which can recover a fully-interpretable solution (i.e., logic formula). Thirdly, to accelerate RL training, we also design a novel critic architecture that enables actor-critic algorithms. Fourthly, to solve hard problems, we propose an incremental training procedure that can learn a logic program progressively. Compared to state-of-the-art (SOTA) differentiable ILP methods, DLM successfully solves all the considered ILP problems with a higher percentage of successful seeds (up to 3.5x). On RL problems, without requiring an interpretable solution, DLM outperforms other non-interpretable neural-logic RL approaches in terms of rewards (up to 3.9%). When enforcing interpretability, DLM can solve harder RL problems (e.g., Sorting, Path) than other interpretable RL methods. Moreover, we show that deep logic programs can be learned via incremental supervised training. In addition to this excellent performance, DLM can scale well in terms of memory and computational time, especially during the testing phase where it can deal with much more constants (>2x) than SOTA.

ICLR Conference 2023 Conference Paper

ERL-Re$^2$: Efficient Evolutionary Reinforcement Learning with Shared State Representation and Individual Policy Representation

  • Jianye Hao
  • Pengyi Li 0001
  • Hongyao Tang
  • Yan Zheng 0002
  • Xian Fu
  • Zhaopeng Meng

Deep Reinforcement Learning (Deep RL) and Evolutionary Algorithm (EA) are two major paradigms of policy optimization with distinct learning principles, i.e., gradient-based v.s. gradient-free. An appealing research direction is integrating Deep RL and EA to devise new methods by fusing their complementary advantages. However, existing works on combining Deep RL and EA have two common drawbacks:1) the RL agent and EA agents learn their policies individually, neglecting efficient sharing of useful common knowledge; 2) parameter-level policy optimization guarantees no semantic level of behavior evolution for the EA side. In this paper, we propose Evolutionary Reinforcement Learning with Two-scale State Representation and Policy Representation (ERL-Re$^2$), a novel solution to the aforementioned two drawbacks. The key idea of ERL-Re$^2$ is two-scale representation: all EA and RL policies share the same nonlinear state representation while maintaining individual linear policy representations. The state representation conveys expressive common features of the environment learned by all the agents collectively; the linear policy representation provides a favorable space for efficient policy optimization, where novel behavior-level crossover and mutation operations can be performed. Moreover, the linear policy representation allows convenient generalization of policy fitness with the help of Policy-extended Value Function Approximator (PeVFA), further improving the sample efficiency of fitness estimation. The experiments on a range of continuous control tasks show that ERL-Re$^2$ consistently outperforms advanced baselines and achieves the State Of The Art (SOTA). Our code is available on https://github.com/yeshenpy/ERL-Re2.

ICLR Conference 2023 Conference Paper

EUCLID: Towards Efficient Unsupervised Reinforcement Learning with Multi-choice Dynamics Model

  • Yifu Yuan
  • Jianye Hao
  • Fei Ni 0001
  • Yao Mu 0001
  • Yan Zheng 0002
  • Yujing Hu
  • Jinyi Liu 0002
  • Yingfeng Chen

Unsupervised reinforcement learning (URL) poses a promising paradigm to learn useful behaviors in a task-agnostic environment without the guidance of extrinsic rewards to facilitate the fast adaptation of various downstream tasks. Previous works focused on the pre-training in a model-free manner while lacking the study of transition dynamics modeling that leaves a large space for the improvement of sample efficiency in downstream tasks. To this end, we propose an Efficient Unsupervised Reinforcement Learning Framework with Multi-choice Dynamics model (EUCLID), which introduces a novel model-fused paradigm to jointly pre-train the dynamics model and unsupervised exploration policy in the pre-training phase, thus better leveraging the environmental samples and improving the downstream task sampling efficiency. However, constructing a generalizable model which captures the local dynamics under different behaviors remains a challenging problem. We introduce the multi-choice dynamics model that covers different local dynamics under different behaviors concurrently, which uses different heads to learn the state transition under different behaviors during unsupervised pre-training and selects the most appropriate head for prediction in the downstream task. Experimental results in the manipulation and locomotion domains demonstrate that EUCLID achieves state-of-the-art performance with high sample efficiency, basically solving the state-based URLB benchmark and reaching a mean normalized score of 104.0±1.2% in downstream tasks with 100k fine-tuning steps, which is equivalent to DDPG’s performance at 2M interactive steps with 20× more data. More visualization videos are released on our homepage.

IJCAI Conference 2023 Conference Paper

Generative Flow Networks for Precise Reward-Oriented Active Learning on Graphs

  • Yinchuan Li
  • Zhigang Li
  • Wenqian Li
  • Yunfeng Shao
  • Yan Zheng
  • Jianye Hao

Many score-based active learning methods have been successfully applied to graph-structured data, aiming to reduce the number of labels and achieve better performance of graph neural networks based on predefined score functions. However, these algorithms struggle to learn policy distributions that are proportional to rewards and have limited exploration capabilities. In this paper, we innovatively formulate the graph active learning problem as a generative process, named GFlowGNN, which generates various samples through sequential actions with probabilities precisely proportional to a predefined reward function. Furthermore, we propose the concept of flow nodes and flow features to efficiently model graphs as flows based on generative flow networks, where the policy network is trained with specially designed rewards. Extensive experiments on real datasets show that the proposed approach has good exploration capability and transferability, outperforming various state-of-the-art methods.

ICLR Conference 2023 Conference Paper

Learnable Behavior Control: Breaking Atari Human World Records via Sample-Efficient Behavior Selection

  • Jiajun Fan
  • Yuzheng Zhuang
  • Yuecheng Liu
  • Jianye Hao
  • Bin Wang 0034
  • Jiangcheng Zhu
  • Hao Wang 0049
  • Shu-Tao Xia

The exploration problem is one of the main challenges in deep reinforcement learning (RL). Recent promising works tried to handle the problem with population-based methods, which collect samples with diverse behaviors derived from a population of different exploratory policies. Adaptive policy selection has been adopted for behavior control. However, the behavior selection space is largely limited by the predefined policy population, which further limits behavior diversity. In this paper, we propose a general framework called Learnable Behavioral Control (LBC) to address the limitation, which a) enables a significantly enlarged behavior selection space via formulating a hybrid behavior mapping from all policies; b) constructs a unified learnable process for behavior selection. We introduce LBC into distributed off-policy actor-critic methods and achieve behavior control via optimizing the selection of the behavior mappings with bandit-based meta-controllers. Our agents have achieved 10077.52% mean human normalized score and surpassed 24 human world records within 1B training frames in the Arcade Learning Environment, which demonstrates our significant state-of-the-art (SOTA) performance without degrading the sample efficiency.

ICML Conference 2023 Conference Paper

MetaDiffuser: Diffusion Model as Conditional Planner for Offline Meta-RL

  • Fei Ni 0001
  • Jianye Hao
  • Yao Mu 0001
  • Yifu Yuan
  • Yan Zheng 0002
  • Bin Wang 0034
  • Zhixuan Liang

Recently, diffusion model shines as a promising backbone for the sequence modeling paradigm in offline reinforcement learning(RL). However, these works mostly lack the generalization ability across tasks with reward or dynamics change. To tackle this challenge, in this paper we propose a task-oriented conditioned diffusion planner for offline meta-RL(MetaDiffuser), which considers the generalization problem as conditional trajectory generation task with contextual representation. The key is to learn a context conditioned diffusion model which can generate task-oriented trajectories for planning across diverse tasks. To enhance the dynamics consistency of the generated trajectories while encouraging trajectories to achieve high returns, we further design a dual-guided module in the sampling process of the diffusion model. The proposed framework enjoys the robustness to the quality of collected warm-start data from the testing task and the flexibility to incorporate with different task representation method. The experiment results on MuJoCo benchmarks show that MetaDiffuser outperforms other strong offline meta-RL baselines, demonstrating the outstanding conditional generation ability of diffusion architecture.

AAAI Conference 2023 Conference Paper

Models as Agents: Optimizing Multi-Step Predictions of Interactive Local Models in Model-Based Multi-Agent Reinforcement Learning

  • Zifan Wu
  • Chao Yu
  • Chen Chen
  • Jianye Hao
  • Hankz Hankui Zhuo

Research in model-based reinforcement learning has made significant progress in recent years. Compared to single-agent settings, the exponential dimension growth of the joint state-action space in multi-agent systems dramatically increases the complexity of the environment dynamics, which makes it infeasible to learn an accurate global model and thus necessitates the use of agent-wise local models. However, during multi-step model rollouts, the prediction of one local model can affect the predictions of other local models in the next step. As a result, local prediction errors can be propagated to other localities and eventually give rise to considerably large global errors. Furthermore, since the models are generally used to predict for multiple steps, simply minimizing one-step prediction errors regardless of their long-term effect on other models may further aggravate the propagation of local errors. To this end, we propose Models as AGents (MAG), a multi-agent model optimization framework that reversely treats the local models as multi-step decision making agents and the current policies as the dynamics during the model rollout process. In this way, the local models are able to consider the multi-step mutual affect between each other before making predictions. Theoretically, we show that the objective of MAG is approximately equivalent to maximizing a lower bound of the true environment return. Experiments on the challenging StarCraft II benchmark demonstrate the effectiveness of MAG.

AAAI Conference 2023 Conference Paper

Neighbor Auto-Grouping Graph Neural Networks for Handover Parameter Configuration in Cellular Network

  • Mehrtash Mehrabi
  • Walid Masoudimansour
  • Yingxue Zhang
  • Jie Chuai
  • Zhitang Chen
  • Mark Coates
  • Jianye Hao
  • Yanhui Geng

The mobile communication enabled by cellular networks is the one of the main foundations of our modern society. Optimizing the performance of cellular networks and providing massive connectivity with improved coverage and user experience has a considerable social and economic impact on our daily life. This performance relies heavily on the configuration of the network parameters. However, with the massive increase in both the size and complexity of cellular networks, network management, especially parameter configuration, is becoming complicated. The current practice, which relies largely on experts' prior knowledge, is not adequate and will require lots of domain experts and high maintenance costs. In this work, we propose a learning-based framework for handover parameter configuration. The key challenge, in this case, is to tackle the complicated dependencies between neighboring cells and jointly optimize the whole network. Our framework addresses this challenge in two ways. First, we introduce a novel approach to imitate how the network responds to different network states and parameter values, called auto-grouping graph convolutional network (AG-GCN). During the parameter configuration stage, instead of solving the global optimization problem, we design a local multi-objective optimization strategy where each cell considers several local performance metrics to balance its own performance and its neighbors. We evaluate our proposed algorithm via a simulator constructed using real network data. We demonstrate that the handover parameters our model can find, achieve better average network throughput compared to those recommended by experts as well as alternative baselines, which can bring better network quality and stability. It has the potential to massively reduce costs arising from human expert intervention and maintenance.

AAMAS Conference 2023 Conference Paper

Off-Beat Multi-Agent Reinforcement Learning

  • Wei Qiu
  • Weixun Wang
  • Rundong Wang
  • Bo An
  • Yujing Hu
  • Svetlana Obraztsova
  • Zinovi Rabinovich
  • Jianye Hao

We investigate cooperative multi-agent reinforcement learning in environments with off-beat actions, i. e. , all actions have execution durations. During execution durations, the environmental changes are not synchronised with action executions. To learn efficient multi-agent coordination in environments with off-beat actions, we propose a novel reward redistribution method built on our novel graph-based episodic memory. We name our solution method as LeGEM. Empirical results on stag-hunter game show that it significantly boosts multi-agent coordination.

ICLR Conference 2023 Conference Paper

Out-of-distribution Detection with Implicit Outlier Transformation

  • Qizhou Wang
  • Junjie Ye 0002
  • Feng Liu 0003
  • Quanyu Dai
  • Marcus Kalander
  • Tongliang Liu
  • Jianye Hao
  • Bo Han 0003

Outlier exposure (OE) is powerful in out-of-distribution (OOD) detection, enhancing detection capability via model fine-tuning with surrogate OOD data. However, surrogate data typically deviate from test OOD data. Thus, the performance of OE when facing unseen OOD data, can be weaken. To address this issue, we propose a novel OE-based approach that makes the model perform well for unseen OOD situations, even for unseen OOD cases. It leads to a min-max learning scheme---searching to synthesize OOD data that leads to worst judgments and learning from such OOD data for the uniform performance in OOD detection. In our realization, these worst OOD data are synthesized by transforming original surrogate ones, where the associated transform functions are learned implicitly based on our novel insight that model perturbation leads to data transformation. Our methodology offers an efficient way of synthesizing OOD data, which can further benefit the detection model, besides the surrogate OOD data. We conduct extensive experiments under various OOD detection setups, demonstrating the effectiveness of our method against its advanced counterparts.

AAMAS Conference 2023 Conference Paper

PORTAL: Automatic Curricula Generation for Multiagent Reinforcement Learning

  • Jizhou Wu
  • Tianpei Yang
  • Xiaotian Hao
  • Jianye Hao
  • Yan Zheng
  • Weixun Wang
  • Matthew E. Taylor

Despite many breakthroughs in recent years, it is still hard for MultiAgent Reinforcement Learning (MARL) algorithms to directly solve complex tasks in MultiAgent Systems (MASs) from scratch. In this work, we study how to use Automatic Curriculum Learning (ACL) to reduce the number of environmental interactions required to learn a good policy. In order to solve a difficult task, ACL methods automatically select a sequence of tasks (i. e. , curricula). The idea is to obtain maximum learning progress towards the final task by continuously learning on tasks that match the current capabilities of the learners. The key question is how to measure the learning progress of the learner for better curriculum selection. We propose a novel ACL framework, PrOgRessive mulTiagent Automatic curricuLum (PORTAL), for MASs. PORTAL selects curricula according to two criteria: 1) How difficult is a task, relative to the learners’ current abilities? 2) How similar is a task, relative to the final task? By learning a shared feature space between tasks, POR- TAL is able to characterize different tasks based on the distribution of features and select those that are similar to the final task. Also, the shared feature space can effectively facilitate the policy transfer between curricula. Experimental results show that PORTAL can train agents to master extremely hard cooperative tasks, which can not be achieved with previous state-of-the-art MARL algorithms. * Corresponding author. Proc. of the 22nd International Conference on Autonomous Agents and Multiagent Systems (AAMAS 2023), A. Ricci, W. Yeoh, N. Agmon, B. An (eds.), May 29 – June 2, 2023, London, United Kingdom. © 2023 International Foundation for Autonomous Agents and Multiagent Systems (www. ifaamas. org). All rights reserved.

ICML Conference 2023 Conference Paper

RACE: Improve Multi-Agent Reinforcement Learning with Representation Asymmetry and Collaborative Evolution

  • Pengyi Li 0001
  • Jianye Hao
  • Hongyao Tang
  • Yan Zheng 0002
  • Xian Fu

Multi-Agent Reinforcement Learning (MARL) has demonstrated its effectiveness in learning collaboration, but it often struggles with low-quality reward signals and high non-stationarity. In contrast, Evolutionary Algorithm (EA) has shown better convergence, robustness, and signal quality insensitivity. This paper introduces a hybrid framework, Representation Asymmetry and Collaboration Evolution (RACE), which combines EA and MARL for efficient collaboration. RACE maintains a MARL team and a population of EA teams. To enable efficient knowledge sharing and policy exploration, RACE decomposes the policies of different teams controlling the same agent into a shared nonlinear observation representation encoder and individual linear policy representations. To address the partial observation issue, we introduce Value-Aware Mutual Information Maximization to enhance the shared representation with useful information about superior global states. EA evolves the population using novel agent-level crossover and mutation operators, offering diverse experiences for MARL. Concurrently, MARL optimizes its policies and injects them into the population for evolution. The experiments on challenging continuous and discrete tasks demonstrate that RACE significantly improves the basic algorithms, consistently outperforming other algorithms. Our code is available at https: //github. com/yeshenpy/RACE.

AAAI Conference 2023 Conference Paper

SplitNet: A Reinforcement Learning Based Sequence Splitting Method for the MinMax Multiple Travelling Salesman Problem

  • Hebin Liang
  • Yi Ma
  • Zilin Cao
  • Tianyang Liu
  • Fei Ni
  • Zhigang Li
  • Jianye Hao

MinMax Multiple Travelling Salesman Problem (mTSP) is an important class of combinatorial optimization problems with many practical applications, of which the goal is to minimize the longest tour of all vehicles. Due to its high computational complexity, existing methods for solving this problem cannot obtain a solution of satisfactory quality with fast speed, especially when the scale of the problem is large. In this paper, we propose a learning-based method named SplitNet to transform the single TSP solutions into the MinMax mTSP solutions of the same instances. Specifically, we generate single TSP solution sequences and split them into mTSP subsequences using an attention-based model trained by reinforcement learning. We also design a decision region for the splitting policy, which significantly reduces the policy action space on instances of various scales and thus improves the generalization ability of SplitNet. The experimental results show that SplitNet generalizes well and outperforms existing learning-based baselines and Google OR-Tools on widely-used random datasets of different scales and public datasets with fast solving speed.

AAAI Conference 2023 Conference Paper

Structure Aware Incremental Learning with Personalized Imitation Weights for Recommender Systems

  • Yuening Wang
  • Yingxue Zhang
  • Antonios Valkanas
  • Ruiming Tang
  • Chen Ma
  • Jianye Hao
  • Mark Coates

Recommender systems now consume large-scale data and play a significant role in improving user experience. Graph Neural Networks (GNNs) have emerged as one of the most effective recommender system models because they model the rich relational information. The ever-growing volume of data can make training GNNs prohibitively expensive. To address this, previous attempts propose to train the GNN models incrementally as new data blocks arrive. Feature and structure knowledge distillation techniques have been explored to allow the GNN model to train in a fast incremental fashion while alleviating the catastrophic forgetting problem. However, preserving the same amount of the historical information for all users is sub-optimal since it fails to take into account the dynamics of each user's change of preferences. For the users whose interests shift substantially, retaining too much of the old knowledge can overly constrain the model, preventing it from quickly adapting to the users’ novel interests. In contrast, for users who have static preferences, model performance can benefit greatly from preserving as much of the user's long-term preferences as possible. In this work, we propose a novel training strategy that adaptively learns personalized imitation weights for each user to balance the contribution from the recent data and the amount of knowledge to be distilled from previous time periods. We demonstrate the effectiveness of learning imitation weights via a comparison on five diverse datasets for three state-of-art structure distillation based recommender systems. The performance shows consistent improvement over competitive incremental learning techniques.

AAMAS Conference 2023 Conference Paper

Transfer Learning based Agent for Automated Negotiation

  • Siqi Chen
  • Qisong Sun
  • Heng You
  • Tianpei Yang
  • Jianye Hao

Although great success has been made in automated negotiation, a major issue still stands out: it is inefficient that learning a policy from scratch when an agent encounters an unknown opponent. Transfer learning (TL) can alleviate this problem by utilizing the knowledge of previously learned policies to accelerate the current task learning. This work presents a novel Transfer Learningbased Negotiating Agent (TLNAgent) framework that allows an autonomous agent to transfer previous knowledge from source policies to help with new tasks, while boosting its performance. TL- NAgent comprises three key components: the negotiation module, the adaptation module and the transfer module. Specifically, the negotiation module is responsible for interacting with the other agent during negotiation. The adaptation module measures the helpfulness of each source policy based on a fusion of two selection mechanisms. The transfer module is based on lateral connections between source and target networks and accelerates the agent’s training by transferring knowledge from the selected source policy. Our comprehensive experiments clearly demonstrate that TL is effective in the context of automated negotiation, and TLNAgent outperforms state-of-the-art negotiating agents in various domains.

UAI Conference 2022 Conference Paper

Cross-domain adaptive transfer reinforcement learning based on state-action correspondence

  • Heng You
  • Tianpei Yang
  • Yan Zheng 0002
  • Jianye Hao
  • Matthew E. Taylor

Despite the impressive success achieved in various domains, deep reinforcement learning (DRL) is still faced with the sample inefficiency problem. Transfer learning (TL), which leverages prior knowledge from different but related tasks to accelerate the target task learning, has emerged as a promising direction to improve RL efficiency. The majority of prior work considers TL across tasks with the same state-action spaces, while transferring across domains with different state-action spaces is relatively unexplored. Furthermore, such existing cross-domain transfer approaches only enable transfer from a single source policy, leaving open the important question of how to best transfer from multiple source policies. This paper proposes a novel framework called Cross-domain Adaptive Transfer (CAT) to accelerate DRL. CAT learns the state-action correspondence from each source task to the target task and adaptively transfers knowledge from multiple source task policies to the target policy. CAT can be easily combined with existing DRL algorithms and experimental results show that CAT significantly accelerates learning and outperforms other cross-domain transfer methods on multiple continuous action control tasks.

NeurIPS Conference 2022 Conference Paper

DOMINO: Decomposed Mutual Information Optimization for Generalized Context in Meta-Reinforcement Learning

  • Yao Mu
  • Yuzheng Zhuang
  • Fei Ni
  • Bin Wang
  • Jianyu Chen
  • Jianye Hao
  • Ping Luo

Adapting to the changes in transition dynamics is essential in robotic applications. By learning a conditional policy with a compact context, context-aware meta-reinforcement learning provides a flexible way to adjust behavior according to dynamics changes. However, in real-world applications, the agent may encounter complex dynamics changes. Multiple confounders can influence the transition dynamics, making it challenging to infer accurate context for decision-making. This paper addresses such a challenge by decomposed mutual information optimization (DOMINO) for context learning, which explicitly learns a disentangled context to maximize the mutual information between the context and historical trajectories while minimizing the state transition prediction error. Our theoretical analysis shows that DOMINO can overcome the underestimation of the mutual information caused by multi-confounded challenges via learning disentangled context and reduce the demand for the number of samples collected in various environments. Extensive experiments show that the context learned by DOMINO benefits both model-based and model-free reinforcement learning algorithms for dynamics generalization in terms of sample efficiency and performance in unseen environments.

NeurIPS Conference 2022 Conference Paper

GALOIS: Boosting Deep Reinforcement Learning via Generalizable Logic Synthesis

  • Yushi Cao
  • Zhiming Li
  • Tianpei Yang
  • Hao Zhang
  • Yan Zheng
  • Yi Li
  • Jianye Hao
  • Yang Liu

Despite achieving superior performance in human-level control problems, unlike humans, deep reinforcement learning (DRL) lacks high-order intelligence (e. g. , logic deduction and reuse), thus it behaves ineffectively than humans regarding learning and generalization in complex problems. Previous works attempt to directly synthesize a white-box logic program as the DRL policy, manifesting logic-driven behaviors. However, most synthesis methods are built on imperative or declarative programming, and each has a distinct limitation, respectively. The former ignores the cause-effect logic during synthesis, resulting in low generalizability across tasks. The latter is strictly proof-based, thus failing to synthesize programs with complex hierarchical logic. In this paper, we combine the above two paradigms together and propose a novel Generalizable Logic Synthesis (GALOIS) framework to synthesize hierarchical and strict cause-effect logic programs. GALOIS leverages the program sketch and defines a new sketch-based hybrid program language for guiding the synthesis. Based on that, GALOIS proposes a sketch-based program synthesis method to automatically generate white-box programs with generalizable and interpretable cause-effect logic. Extensive evaluations on various decision-making tasks with complex logic demonstrate the superiority of GALOIS over mainstream baselines regarding the asymptotic performance, generalizability, and great knowledge reusability across different environments.

ICLR Conference 2022 Conference Paper

HyAR: Addressing Discrete-Continuous Action Reinforcement Learning via Hybrid Action Representation

  • Boyan Li
  • Hongyao Tang
  • Yan Zheng 0002
  • Jianye Hao
  • Pengyi Li 0001
  • Zhen Wang 0004
  • Zhaopeng Meng
  • Li Wang

Discrete-continuous hybrid action space is a natural setting in many practical problems, such as robot control and game AI. However, most previous Reinforcement Learning (RL) works only demonstrate the success in controlling with either discrete or continuous action space, while seldom take into account the hybrid action space. One naive way to address hybrid action RL is to convert the hybrid action space into a unified homogeneous action space by discretization or continualization, so that conventional RL algorithms can be applied. However, this ignores the underlying structure of hybrid action space and also induces the scalability issue and additional approximation difficulties, thus leading to degenerated results. In this paper, we propose Hybrid Action Representation (HyAR) to learn a compact and decodable latent representation space for the original hybrid action space. HyAR constructs the latent space and embeds the dependence between discrete action and continuous parameter via an embedding table and conditional Variantional Auto-Encoder (VAE). To further improve the effectiveness, the action representation is trained to be semantically smooth through unsupervised environmental dynamics prediction. Finally, the agent then learns its policy with conventional DRL algorithms in the learned representation space and interacts with the environment by decoding the hybrid action embeddings to the original action space. We evaluate HyAR in a variety of environments with discrete-continuous action space. The results demonstrate the superiority of HyAR when compared with previous baselines, especially for high-dimensional action spaces.

ICML Conference 2022 Conference Paper

Individual Reward Assisted Multi-Agent Reinforcement Learning

  • Li Wang
  • Yupeng Zhang
  • Yujing Hu
  • Weixun Wang
  • Chongjie Zhang
  • Yang Gao 0001
  • Jianye Hao
  • Tangjie Lv

In many real-world multi-agent systems, the sparsity of team rewards often makes it difficult for an algorithm to successfully learn a cooperative team policy. At present, the common way for solving this problem is to design some dense individual rewards for the agents to guide the cooperation. However, most existing works utilize individual rewards in ways that do not always promote teamwork and sometimes are even counterproductive. In this paper, we propose Individual Reward Assisted Team Policy Learning (IRAT), which learns two policies for each agent from the dense individual reward and the sparse team reward with discrepancy constraints for updating the two policies mutually. Experimental results in different scenarios, such as the Multi-Agent Particle Environment and the Google Research Football Environment, show that IRAT significantly outperforms the baseline methods and can greatly promote team policy learning without deviating from the original team objective, even when the individual rewards are misleading or conflict with the team rewards.

ICML Conference 2022 Conference Paper

Learning Pseudometric-based Action Representations for Offline Reinforcement Learning

  • Pengjie Gu
  • Mengchen Zhao
  • Chen Chen 0077
  • Dong Li 0016
  • Jianye Hao
  • Bo An 0001

Offline reinforcement learning is a promising approach for practical applications since it does not require interactions with real-world environments. However, existing offline RL methods only work well in environments with continuous or small discrete action spaces. In environments with large and discrete action spaces, such as recommender systems and dialogue systems, the performance of existing methods decreases drastically because they suffer from inaccurate value estimation for a large proportion of out-of-distribution (o. o. d.) actions. While recent works have demonstrated that online RL benefits from incorporating semantic information in action representations, unfortunately, they fail to learn reasonable relative distances between action representations, which is key to offline RL to reduce the influence of o. o. d. actions. This paper proposes an action representation learning framework for offline RL based on a pseudometric, which measures both the behavioral relation and the data-distributional relation between actions. We provide theoretical analysis on the continuity of the expected Q-values and the offline policy improvement using the learned action representations. Experimental results show that our methods significantly improve the performance of two typical offline RL methods in environments with large and discrete action spaces.

ICLR Conference 2022 Conference Paper

Learning State Representations via Retracing in Reinforcement Learning

  • Changmin Yu
  • Dong Li 0016
  • Jianye Hao
  • Jun Wang 0012
  • Neil Burgess

We propose learning via retracing, a novel self-supervised approach for learning the state representation (and the associated dynamics model) for reinforcement learning tasks. In addition to the predictive (reconstruction) supervision in the forward direction, we propose to include "retraced" transitions for representation/model learning, by enforcing the cycle-consistency constraint between the original and retraced states, hence improve upon the sample efficiency of learning. Moreover, learning via retracing explicitly propagates information about future transitions backward for inferring previous states, thus facilitates stronger representation learning for the downstream reinforcement learning tasks. We introduce Cycle-Consistency World Model (CCWM), a concrete model-based instantiation of learning via retracing. Additionally we propose a novel adaptive "truncation" mechanism for counteracting the negative impacts brought by "irreversible" transitions such that learning via retracing can be maximally effective. Through extensive empirical studies on visual-based continuous control benchmarks, we demonstrate that CCWM achieves state-of-the-art performance in terms of sample efficiency and asymptotic performance, whilst exhibiting behaviours that are indicative of stronger representation learning.

AAMAS Conference 2022 Conference Paper

Multiagent Q-learning with Sub-Team Coordination

  • Wenhan Huang
  • Kai Li
  • Kun Shao
  • Tianze Zhou
  • Jun Luo
  • Dongge Wang
  • Hangyu Mao
  • Jianye Hao

For cooperative mutliagent reinforcement learning tasks, we propose a novel value factorization framework in the popular centralized training with decentralized execution paradigm, called multiagent Q-learning with sub-team coordination (QSCAN). This framework could flexibly exploit local coordination within sub-teams for effective factorization while honoring the individual-globalmax (IGM) condition. QSCAN encompasses the full spectrum of sub-team coordination according to sub-team size, ranging from the monotonic value function class to the entire IGM function class, with familiar methods such as QMIX and QPLEX located at the respective extremes of the spectrum. Empirical results show that QSCAN’s performance dominates state-of-the-art methods in predator-prey tasks and the Switch challenge in MA-Gym.

NeurIPS Conference 2022 Conference Paper

Multiagent Q-learning with Sub-Team Coordination

  • Wenhan Huang
  • Kai Li
  • Kun Shao
  • Tianze Zhou
  • Matthew Taylor
  • Jun Luo
  • Dongge Wang
  • Hangyu Mao

In many real-world cooperative multiagent reinforcement learning (MARL) tasks, teams of agents can rehearse together before deployment, but then communication constraints may force individual agents to execute independently when deployed. Centralized training and decentralized execution (CTDE) is increasingly popular in recent years, focusing mainly on this setting. In the value-based MARL branch, credit assignment mechanism is typically used to factorize the team reward into each individual’s reward — individual-global-max (IGM) is a condition on the factorization ensuring that agents’ action choices coincide with team’s optimal joint action. However, current architectures fail to consider local coordination within sub-teams that should be exploited for more effective factorization, leading to faster learning. We propose a novel value factorization framework, called multiagent Q-learning with sub-team coordination (QSCAN), to flexibly represent sub-team coordination while honoring the IGM condition. QSCAN encompasses the full spectrum of sub-team coordination according to sub-team size, ranging from the monotonic value function class to the entire IGM function class, with familiar methods such as QMIX and QPLEX located at the respective extremes of the spectrum. Experimental results show that QSCAN’s performance dominates state-of-the-art methods in matrix games, predator-prey tasks, the Switch challenge in MA-Gym. Additionally, QSCAN achieves comparable performances to those methods in a selection of StarCraft II micro-management tasks.

ICML Conference 2022 Conference Paper

Neuro-Symbolic Hierarchical Rule Induction

  • Claire Glanois
  • Zhao-Hui Jiang
  • Xuening Feng
  • Paul Weng
  • Matthieu Zimmer
  • Dong Li 0016
  • Wulong Liu
  • Jianye Hao

We propose Neuro-Symbolic Hierarchical Rule Induction, an efficient interpretable neuro-symbolic model, to solve Inductive Logic Programming (ILP) problems. In this model, which is built from a pre-defined set of meta-rules organized in a hierarchical structure, first-order rules are invented by learning embeddings to match facts and body predicates of a meta-rule. To instantiate, we specifically design an expressive set of generic meta-rules, and demonstrate they generate a consequent fragment of Horn clauses. As a differentiable model, HRI can be trained both via supervised learning and reinforcement learning. To converge to interpretable rules, we inject a controlled noise to avoid local optima and employ an interpretability-regularization term. We empirically validate our model on various tasks (ILP, visual genome, reinforcement learning) against relevant state-of-the-art methods, including traditional ILP methods and neuro-symbolic models.

ICLR Conference 2022 Conference Paper

Online Ad Hoc Teamwork under Partial Observability

  • Pengjie Gu
  • Mengchen Zhao
  • Jianye Hao
  • Bo An 0001

Autonomous agents often need to work together as a team to accomplish complex cooperative tasks. Due to privacy and other realistic constraints, agents might need to collaborate with previously unknown teammates on the fly. This problem is known as ad hoc teamwork, which remains a core research challenge. Prior works usually rely heavily on strong assumptions like full observability, fixed and predefined teammates' types. This paper relaxes these assumptions with a novel reinforcement learning framework called ODITS, which allows the autonomous agent to adapt to arbitrary teammates in an online fashion. Instead of limiting teammates into a finite set of predefined types, ODITS automatically learns latent variables of teammates' behaviors to infer how to cooperate with new teammates effectively. To overcome partial observability, we introduce an information-based regularizer to derive proxy representations of the learned variables from local observations. Extensive experimental results show that ODITS significantly outperforms various baselines in widely used ad hoc teamwork tasks.

IJCAI Conference 2022 Conference Paper

PAnDR: Fast Adaptation to New Environments from Offline Experiences via Decoupling Policy and Environment Representations

  • Tong Sang
  • Hongyao Tang
  • Yi Ma
  • Jianye Hao
  • Yan Zheng
  • Zhaopeng Meng
  • Boyan Li
  • Zhen Wang

Deep Reinforcement Learning (DRL) has been a promising solution to many complex decision-making problems. Nevertheless, the notorious weakness in generalization among environments prevent widespread application of DRL agents in real-world scenarios. Although advances have been made recently, most prior works assume sufficient online interaction on training environments, which can be costly in practical cases. To this end, we focus on an offline-training-online-adaptation setting, in which the agent first learns from offline experiences collected in environments with different dynamics and then performs online policy adaptation in environments with new dynamics. In this paper, we propose Policy Adaptation with Decoupled Representations (PAnDR) for fast policy adaptation. In offline training phase, the environment representation and policy representation are learned through contrastive learning and policy recovery, respectively. The representations are further refined by mutual information optimization to make them more decoupled and complete. With learned representations, a Policy-Dynamics Value Function (PDVF) network is trained to approximate the values for different combinations of policies and environments from offline experiences. In online adaptation phase, with the environment context inferred from few experiences collected in new environments, the policy is optimized by gradient ascent with respect to the PDVF. Our experiments show that PAnDR outperforms existing algorithms in several representative policy adaptation problems.

NeurIPS Conference 2022 Conference Paper

Plan To Predict: Learning an Uncertainty-Foreseeing Model For Model-Based Reinforcement Learning

  • Zifan Wu
  • Chao Yu
  • Chen Chen
  • Jianye Hao
  • Hankz Hankui Zhuo

In Model-based Reinforcement Learning (MBRL), model learning is critical since an inaccurate model can bias policy learning via generating misleading samples. However, learning an accurate model can be difficult since the policy is continually updated and the induced distribution over visited states used for model learning shifts accordingly. Prior methods alleviate this issue by quantifying the uncertainty of model-generated samples. However, these methods only quantify the uncertainty passively after the samples were generated, rather than foreseeing the uncertainty before model trajectories fall into those highly uncertain regions. The resulting low-quality samples can induce unstable learning targets and hinder the optimization of the policy. Moreover, while being learned to minimize one-step prediction errors, the model is generally used to predict for multiple steps, leading to a mismatch between the objectives of model learning and model usage. To this end, we propose Plan To Predict (P2P), an MBRL framework that treats the model rollout process as a sequential decision making problem by reversely considering the model as a decision maker and the current policy as the dynamics. In this way, the model can quickly adapt to the current policy and foresee the multi-step future uncertainty when generating trajectories. Theoretically, we show that the performance of P2P can be guaranteed by approximately optimizing a lower bound of the true environment return. Empirical results demonstrate that P2P achieves state-of-the-art performance on several challenging benchmark tasks.

ICML Conference 2022 Conference Paper

Plan Your Target and Learn Your Skills: Transferable State-Only Imitation Learning via Decoupled Policy Optimization

  • Minghuan Liu
  • Zhengbang Zhu
  • Yuzheng Zhuang
  • Weinan Zhang 0001
  • Jianye Hao
  • Yong Yu 0001
  • Jun Wang 0012

Recent progress in state-only imitation learning extends the scope of applicability of imitation learning to real-world settings by relieving the need for observing expert actions. However, existing solutions only learn to extract a state-to-action mapping policy from the data, without considering how the expert plans to the target. This hinders the ability to leverage demonstrations and limits the flexibility of the policy. In this paper, we introduce Decoupled Policy Optimization (DePO), which explicitly decouples the policy as a high-level state planner and an inverse dynamics model. With embedded decoupled policy gradient and generative adversarial training, DePO enables knowledge transfer to different action spaces or state transition dynamics, and can generalize the planner to out-of-demonstration state regions. Our in-depth experimental analysis shows the effectiveness of DePO on learning a generalized target state planner while achieving the best imitation performance. We demonstrate the appealing usage of DePO for transferring across different tasks by pre-training, and the potential for co-training agents with various skills.

ICML Conference 2022 Conference Paper

PMIC: Improving Multi-Agent Reinforcement Learning with Progressive Mutual Information Collaboration

  • Pengyi Li 0001
  • Hongyao Tang
  • Tianpei Yang
  • Xiaotian Hao
  • Tong Sang
  • Yan Zheng 0002
  • Jianye Hao
  • Matthew E. Taylor

Learning to collaborate is critical in Multi-Agent Reinforcement Learning (MARL). Previous works promote collaboration by maximizing the correlation of agents’ behaviors, which is typically characterized by Mutual Information (MI) in different forms. However, we reveal sub-optimal collaborative behaviors also emerge with strong correlations, and simply maximizing the MI can, surprisingly, hinder the learning towards better collaboration. To address this issue, we propose a novel MARL framework, called Progressive Mutual Information Collaboration (PMIC), for more effective MI-driven collaboration. PMIC uses a new collaboration criterion measured by the MI between global states and joint actions. Based on this criterion, the key idea of PMIC is maximizing the MI associated with superior collaborative behaviors and minimizing the MI associated with inferior ones. The two MI objectives play complementary roles by facilitating better collaborations while avoiding falling into sub-optimal ones. Experiments on a wide range of MARL benchmarks show the superior performance of PMIC compared with other algorithms.

ICRA Conference 2022 Conference Paper

Promoting Quality and Diversity in Population-based Reinforcement Learning via Hierarchical Trajectory Space Exploration

  • Jiayu Miao
  • Tianze Zhou
  • Kun Shao
  • Ming Zhou 0006
  • Weinan Zhang 0001
  • Jianye Hao
  • Yong Yu 0001
  • Jun Wang 0012

Quality Diversity (QD) algorithms in population-based reinforcement learning aim to optimize agents' returns and diversity among the population simultaneously. It is conducive to solving exploration problems in reinforcement learning and potentially getting multiple good and diverse strategies. However, previous methods typically define behavioral embedding in action space or outcome space, which neglect trajectory characteristics during the execution process. In this paper, we introduce a trajectory embedding model trained by Variational Autoencoder with similarity constraint to characterize trajectory features. Based on that, we propose a hierarchical trajectory-space exploration (HTSE) framework using Determinantal Point Processes (DPP) to generate high-quality and diverse solutions in the selection and mutation process. The experimental results show that our HTSE method effectively completes several simulated tasks, outperforming other Quality-Diversity Reinforcement Learning algorithms.

NeurIPS Conference 2022 Conference Paper

The Policy-gradient Placement and Generative Routing Neural Networks for Chip Design

  • Ruoyu Cheng
  • Xianglong Lyu
  • Yang Li
  • Junjie Ye
  • Jianye Hao
  • Junchi Yan

Placement and routing are two critical yet time-consuming steps of chip design in modern VLSI systems. Distinct from traditional heuristic solvers, this paper on one hand proposes an RL-based model for mixed-size macro placement, which differs from existing learning-based placers that often consider the macro by coarse grid-based mask. While the standard cells are placed via gradient-based GPU acceleration. On the other hand, a one-shot conditional generative routing model, which is composed of a special-designed input-size-adapting generator and a bi-discriminator, is devised to perform one-shot routing to the pins within each net, and the order of nets to route is adaptively learned. Combining these techniques, we develop a flexible and efficient neural pipeline, which to our best knowledge, is the first joint placement and routing network without involving any traditional heuristic solver. Experimental results on chip design benchmarks showcase the effectiveness of our approach, with code that will be made publicly available.

NeurIPS Conference 2022 Conference Paper

Transformer-based Working Memory for Multiagent Reinforcement Learning with Action Parsing

  • Yaodong Yang
  • Guangyong Chen
  • Weixun Wang
  • Xiaotian Hao
  • Jianye Hao
  • Pheng-Ann Heng

Learning in real-world multiagent tasks is challenging due to the usual partial observability of each agent. Previous efforts alleviate the partial observability by historical hidden states with Recurrent Neural Networks, however, they do not consider the multiagent characters that either the multiagent observation consists of a number of object entities or the action space shows clear entity interactions. To tackle these issues, we propose the Agent Transformer Memory (ATM) network with a transformer-based memory. First, ATM utilizes the transformer to enable the unified processing of the factored environmental entities and memory. Inspired by the human’s working memory process where a limited capacity of information temporarily held in mind can effectively guide the decision-making, ATM updates its fixed-capacity memory with the working memory updating schema. Second, as agents' each action has its particular interaction entities in the environment, ATM parses the action space to introduce this action’s semantic inductive bias by binding each action with its specified involving entity to predict the state-action value or logit. Extensive experiments on the challenging SMAC and Level-Based Foraging environments validate that ATM could boost existing multiagent RL algorithms with impressive learning acceleration and performance improvement.

NeurIPS Conference 2022 Conference Paper

Versatile Multi-stage Graph Neural Network for Circuit Representation

  • Shuwen Yang
  • Zhihao Yang
  • Dong Li
  • Yingxueff Zhang
  • Zhanguang Zhang
  • Guojie Song
  • Jianye Hao

Due to the rapid growth in the scale of circuits and the desire for knowledge transfer from old designs to new ones, deep learning technologies have been widely exploited in Electronic Design Automation (EDA) to assist circuit design. In chip design cycles, we might encounter heterogeneous and diverse information sources, including the two most informative ones: the netlist and the design layout. However, handling each information source independently is sub-optimal. In this paper, we propose a novel way to integrate the multiple information sources under a unified heterogeneous graph named Circuit Graph, where topological and geometrical information is well integrated. Then, we propose Circuit GNN to fully utilize the features of vertices, edges as well as heterogeneous information during the message passing process. It is the first attempt to design a versatile circuit representation that is compatible across multiple EDA tasks and stages. Experiments on the two most representative prediction tasks in EDA show that our solution reaches state-of-the-art performance in both logic synthesis and global placement chip design stages. Besides, it achieves a 10x speed-up on congestion prediction compared to the state-of-the-art model.

AAAI Conference 2022 Conference Paper

What about Inputting Policy in Value Function: Policy Representation and Policy-Extended Value Function Approximator

  • Hongyao Tang
  • Zhaopeng Meng
  • Jianye Hao
  • Chen Chen
  • Daniel Graves
  • Dong Li
  • Changmin Yu
  • Hangyu Mao

We study Policy-extended Value Function Approximator (PeVFA) in Reinforcement Learning (RL), which extends conventional value function approximator (VFA) to take as input not only the state (and action) but also an explicit policy representation. Such an extension enables PeVFA to preserve values of multiple policies at the same time and brings an appealing characteristic, i. e. , value generalization among policies. We formally analyze the value generalization under Generalized Policy Iteration (GPI). From theoretical and empirical lens, we show that generalized value estimates offered by PeVFA may have lower initial approximation error to true values of successive policies, which is expected to improve consecutive value approximation during GPI. Based on above clues, we introduce a new form of GPI with PeVFA which leverages the value generalization along policy improvement path. Moreover, we propose a representation learning framework for RL policy, providing several approaches to learn effective policy embeddings from policy network parameters or stateaction pairs. In our experiments, we evaluate the efficacy of value generalization offered by PeVFA and policy representation learning in several OpenAI Gym continuous control tasks. For a representative instance of algorithm implementation, Proximal Policy Optimization (PPO) re-implemented under the paradigm of GPI with PeVFA achieves about 40% performance improvement on its vanilla counterpart in most environments.

NeurIPS Conference 2021 Conference Paper

A Hierarchical Reinforcement Learning Based Optimization Framework for Large-scale Dynamic Pickup and Delivery Problems

  • Yi Ma
  • Xiaotian Hao
  • Jianye Hao
  • Jiawen Lu
  • Xing Liu
  • Tong Xialiang
  • Mingxuan Yuan
  • Zhigang Li

The Dynamic Pickup and Delivery Problem (DPDP) is an essential problem in the logistics domain, which is NP-hard. The objective is to dynamically schedule vehicles among multiple sites to serve the online generated orders such that the overall transportation cost could be minimized. The critical challenge of DPDP is the orders are not known a priori, i. e. , the orders are dynamically generated in real-time. To address this problem, existing methods partition the overall DPDP into fixed-size sub-problems by caching online generated orders and solve each sub-problem, or on this basis to utilize the predicted future orders to optimize each sub-problem further. However, the solution quality and efficiency of these methods are unsatisfactory, especially when the problem scale is very large. In this paper, we propose a novel hierarchical optimization framework to better solve large-scale DPDPs. Specifically, we design an upper-level agent to dynamically partition the DPDP into a series of sub-problems with different scales to optimize vehicles routes towards globally better solutions. Besides, a lower-level agent is designed to efficiently solve each sub-problem by incorporating the strengths of classical operational research-based methods with reinforcement learning-based policies. To verify the effectiveness of the proposed framework, real historical data is collected from the order dispatching system of Huawei Supply Chain Business Unit and used to build a functional simulator. Extensive offline simulation and online testing conducted on the industrial order dispatching system justify the superior performance of our framework over existing baselines.

NeurIPS Conference 2021 Conference Paper

Adaptive Online Packing-guided Search for POMDPs

  • Chenyang Wu
  • Guoyu Yang
  • Zongzhang Zhang
  • Yang Yu
  • Dong Li
  • Wulong Liu
  • Jianye Hao

The partially observable Markov decision process (POMDP) provides a general framework for modeling an agent's decision process with state uncertainty, and online planning plays a pivotal role in solving it. A belief is a distribution of states representing state uncertainty. Methods for large-scale POMDP problems rely on the same idea of sampling both states and observations. That is, instead of exact belief updating, a collection of sampled states is used to approximate the belief; instead of considering all possible observations, only a set of sampled observations are considered. Inspired by this, we take one step further and propose an online planning algorithm, Adaptive Online Packing-guided Search (AdaOPS), to better approximate beliefs with adaptive particle filter technique and balance estimation bias and variance by fusing similar observation branches. Theoretically, our algorithm is guaranteed to find an $\epsilon$-optimal policy with a high probability given enough planning time under some mild assumptions. We evaluate our algorithm on several tricky POMDP domains, and it outperforms the state-of-the-art in all of them.

AAAI Conference 2021 Conference Paper

Addressing Action Oscillations through Learning Policy Inertia

  • Chen Chen
  • Hongyao Tang
  • Jianye Hao
  • Wulong Liu
  • Zhaopeng Meng

Deep reinforcement learning (DRL) algorithms have been demonstrated to be effective in a wide range of challenging decision making and control tasks. However, these methods typically suffer from severe action oscillations in particular in discrete action setting, which means that agents select different actions within consecutive steps even though states only slightly differ. This issue is often neglected since the policy is usually evaluated by its cumulative rewards only. Action oscillation strongly affects the user experience and can even cause serious potential security menace especially in realworld domains with the main concern of safety, such as autonomous driving. To this end, we introduce Policy Inertia Controller (PIC) which serves as a generic plug-in framework to off-the-shelf DRL algorithms, to enables adaptive trade-off between the optimality and smoothness of the learned policy in a formal way. We propose Nested Policy Iteration as a general training algorithm for PIC-augmented policy which ensures monotonically non-decreasing updates under some mild conditions. Further, we derive a practical DRL algorithm, namely Nested Soft Actor-Critic. Experiments on a collection of autonomous driving tasks and several Atari games suggest that our approach demonstrates substantial oscillation reduction in comparison to a range of commonly adopted baselines with almost no performance degradation.

NeurIPS Conference 2021 Conference Paper

An Efficient Transfer Learning Framework for Multiagent Reinforcement Learning

  • Tianpei Yang
  • Weixun Wang
  • Hongyao Tang
  • Jianye Hao
  • Zhaopeng Meng
  • Hangyu Mao
  • Dong Li
  • Wulong Liu

Transfer Learning has shown great potential to enhance single-agent Reinforcement Learning (RL) efficiency. Similarly, Multiagent RL (MARL) can also be accelerated if agents can share knowledge with each other. However, it remains a problem of how an agent should learn from other agents. In this paper, we propose a novel Multiagent Policy Transfer Framework (MAPTF) to improve MARL efficiency. MAPTF learns which agent's policy is the best to reuse for each agent and when to terminate it by modeling multiagent policy transfer as the option learning problem. Furthermore, in practice, the option module can only collect all agent's local experiences for update due to the partial observability of the environment. While in this setting, each agent's experience may be inconsistent with each other, which may cause the inaccuracy and oscillation of the option-value's estimation. Therefore, we propose a novel option learning algorithm, the successor representation option learning to solve it by decoupling the environment dynamics from rewards and learning the option-value under each agent's preference. MAPTF can be easily combined with existing deep RL and MARL approaches, and experimental results show it significantly boosts the performance of existing methods in both discrete and continuous state spaces.

NeurIPS Conference 2021 Conference Paper

Dynamic Bottleneck for Robust Self-Supervised Exploration

  • Chenjia Bai
  • Lingxiao Wang
  • Lei Han
  • Animesh Garg
  • Jianye Hao
  • Peng Liu
  • Zhaoran Wang

Exploration methods based on pseudo-count of transitions or curiosity of dynamics have achieved promising results in solving reinforcement learning with sparse rewards. However, such methods are usually sensitive to environmental dynamics-irrelevant information, e. g. , white-noise. To handle such dynamics-irrelevant information, we propose a Dynamic Bottleneck (DB) model, which attains a dynamics-relevant representation based on the information-bottleneck principle. Based on the DB model, we further propose DB-bonus, which encourages the agent to explore state-action pairs with high information gain. We establish theoretical connections between the proposed DB-bonus, the upper confidence bound (UCB) for linear case, and the visiting count for tabular case. We evaluate the proposed method on Atari suits with dynamics-irrelevant noises. Our experiments show that exploration with DB bonus outperforms several state-of-the-art exploration methods in noisy environments.

NeurIPS Conference 2021 Conference Paper

Flattening Sharpness for Dynamic Gradient Projection Memory Benefits Continual Learning

  • Danruo Deng
  • Guangyong Chen
  • Jianye Hao
  • Qiong Wang
  • Pheng-Ann Heng

The backpropagation networks are notably susceptible to catastrophic forgetting, where networks tend to forget previously learned skills upon learning new ones. To address such the 'sensitivity-stability' dilemma, most previous efforts have been contributed to minimizing the empirical risk with different parameter regularization terms and episodic memory, but rarely exploring the usages of the weight loss landscape. In this paper, we investigate the relationship between the weight loss landscape and sensitivity-stability in the continual learning scenario, based on which, we propose a novel method, Flattening Sharpness for Dynamic Gradient Projection Memory (FS-DGPM). In particular, we introduce a soft weight to represent the importance of each basis representing past tasks in GPM, which can be adaptively learned during the learning process, so that less important bases can be dynamically released to improve the sensitivity of new skill learning. We further introduce Flattening Sharpness (FS) to reduce the generalization gap by explicitly regulating the flatness of the weight loss landscape of all seen tasks. As demonstrated empirically, our proposed method consistently outperforms baselines with the superior ability to learn new skills while alleviating forgetting effectively.

AAAI Conference 2021 Conference Paper

Foresee then Evaluate: Decomposing Value Estimation with Latent Future Prediction

  • Hongyao Tang
  • Zhaopeng Meng
  • Guangyong Chen
  • Pengfei Chen
  • Chen Chen
  • Yaodong Yang
  • Luo Zhang
  • Wulong Liu

Value function is the central notion of Reinforcement Learning (RL). Value estimation, especially with function approximation, can be challenging since it involves the stochasticity of environmental dynamics and reward signals that can be sparse and delayed in some cases. A typical model-free RL algorithm usually estimates the values of a policy by Temporal Difference (TD) or Monte Carlo (MC) algorithms directly from rewards, without explicitly taking dynamics into consideration. In this paper, we propose Value Decomposition with Future Prediction (VDFP), providing an explicit two-step understanding of the value estimation process: 1) first foresee the latent future, 2) and then evaluate it. We analytically decompose the value function into a latent future dynamics part and a policy-independent trajectory return part, inducing a way to model latent dynamics and returns separately in value estimation. Further, we derive a practical deep RL algorithm, consisting of a convolutional model to learn compact trajectory representation from past experiences, a conditional variational auto-encoder to predict the latent future dynamics and a convex return model that evaluates trajectory representation. In experiments, we empirically demonstrate the effectiveness of our approach for both off-policy and on-policy RL in several OpenAI Gym continuous control tasks as well as a few challenging variants with delayed reward.

NeurIPS Conference 2021 Conference Paper

Model-Based Reinforcement Learning via Imagination with Derived Memory

  • Yao Mu
  • Yuzheng Zhuang
  • Bin Wang
  • Guangxiang Zhu
  • Wulong Liu
  • Jianyu Chen
  • Ping Luo
  • Shengbo Li

Model-based reinforcement learning aims to improve the sample efficiency of policy learning by modeling the dynamics of the environment. Recently, the latent dynamics model is further developed to enable fast planning in a compact space. It summarizes the high-dimensional experiences of an agent, which mimics the memory function of humans. Learning policies via imagination with the latent model shows great potential for solving complex tasks. However, only considering memories from the true experiences in the process of imagination could limit its advantages. Inspired by the memory prosthesis proposed by neuroscientists, we present a novel model-based reinforcement learning framework called Imagining with Derived Memory (IDM). It enables the agent to learn policy from enriched diverse imagination with prediction-reliability weight, thus improving sample efficiency and policy robustness. Experiments on various high-dimensional visual control tasks in the DMControl benchmark demonstrate that IDM outperforms previous state-of-the-art methods in terms of policy robustness and further improves the sample efficiency of the model-based method.

IJCAI Conference 2021 Conference Paper

Ordering-Based Causal Discovery with Reinforcement Learning

  • Xiaoqiang Wang
  • Yali Du
  • Shengyu Zhu
  • Liangjun Ke
  • Zhitang Chen
  • Jianye Hao
  • Jun Wang

It is a long-standing question to discover causal relations among a set of variables in many empirical sciences. Recently, Reinforcement Learning (RL) has achieved promising results in causal discovery from observational data. However, searching the space of directed graphs and enforcing acyclicity by implicit penalties tend to be inefficient and restrict the existing RL-based method to small scale problems. In this work, we propose a novel RL-based approach for causal discovery, by incorporating RL into the ordering-based paradigm. Specifically, we formulate the ordering search problem as a multi-step Markov decision process, implement the ordering generating process with an encoder-decoder architecture, and finally use RL to optimize the proposed model based on the reward mechanisms designed for each ordering. A generated ordering would then be processed using variable selection to obtain the final causal graph. We analyze the consistency and computational complexity of the proposed method, and empirically show that a pretrained model can be exploited to accelerate training. Experimental results on both synthetic and real data sets shows that the proposed method achieves a much improved performance over existing RL-based method.

ICML Conference 2021 Conference Paper

Principled Exploration via Optimistic Bootstrapping and Backward Induction

  • Chenjia Bai
  • Lingxiao Wang 0003
  • Lei Han 0001
  • Jianye Hao
  • Animesh Garg
  • Peng Liu 0008
  • Zhaoran Wang 0001

One principled approach for provably efficient exploration is incorporating the upper confidence bound (UCB) into the value function as a bonus. However, UCB is specified to deal with linear and tabular settings and is incompatible with Deep Reinforcement Learning (DRL). In this paper, we propose a principled exploration method for DRL through Optimistic Bootstrapping and Backward Induction (OB2I). OB2I constructs a general-purpose UCB-bonus through non-parametric bootstrap in DRL. The UCB-bonus estimates the epistemic uncertainty of state-action pairs for optimistic exploration. We build theoretical connections between the proposed UCB-bonus and the LSVI-UCB in linear setting. We propagate future uncertainty in a time-consistent manner through episodic backward update, which exploits the theoretical advantage and empirically improves the sample-efficiency. Our experiments in MNIST maze and Atari suit suggest that OB2I outperforms several state-of-the-art exploration approaches.

ICRA Conference 2021 Conference Paper

Relational Navigation Learning in Continuous Action Space among Crowds

  • Xueyou Zhang
  • Wei Xi 0002
  • Xian Guo
  • Yongchun Fang
  • Bin Wang 0034
  • Wulong Liu
  • Jianye Hao

In this paper, a novel navigation learning method in continuous action space among crowds based on relational graph is proposed which can be directly deployed on differential-drive mobile robots without any change. More specifically, in order to increase generalization ability in crowd sizes, Graph Convolutional Network (GCN) is at first adopted to extract the relationships between robot and pedestrians. Then the relation features are further utilized as the inputs of the pedestrian state prediction network, the actor network, and the critic network. To efficiently and safely learn the navigation policy, all networks are pretrained through imitating ORCA which is a state-of-the-art algorithm in crowd navigation, and then a model-based reinforcement learning (RL) method which combines the model prediction and the clipped advantage-weighted regression is proposed to finetune the networks. Finally, simulation experiments are performed and it’s verified that the proposed learning method performs significantly better than ORCA and the other state-of-the-art RL methods.

AAAI Conference 2021 Conference Paper

Towards Effective Context for Meta-Reinforcement Learning: an Approach based on Contrastive Learning

  • Haotian Fu
  • Hongyao Tang
  • Jianye Hao
  • Chen Chen
  • Xidong Feng
  • Dong Li
  • Wulong Liu

Context, the embedding of previous collected trajectories, is a powerful construct for Meta-Reinforcement Learning (Meta- RL) algorithms. By conditioning on an effective context, Meta-RL policies can easily generalize to new tasks within a few adaptation steps. We argue that improving the quality of context involves answering two questions: 1. How to train a compact and sufficient encoder that can embed the taskspecific information contained in prior trajectories? 2. How to collect informative trajectories of which the corresponding context reflects the specification of tasks? To this end, we propose a novel Meta-RL framework called CCM (Contrastive learning augmented Context-based Meta-RL). We first focus on the contrastive nature behind different tasks and leverage it to train a compact and sufficient context encoder. Further, we train a separate exploration policy and theoretically derive a new information-gain-based objective which aims to collect informative trajectories in a few steps. Empirically, we evaluate our approaches on common benchmarks as well as several complex sparse-reward environments. The experimental results show that CCM outperforms state-of-the-art algorithms by addressing previously mentioned problems respectively.

ICLR Conference 2020 Conference Paper

Action Semantics Network: Considering the Effects of Actions in Multiagent Systems

  • Weixun Wang
  • Tianpei Yang
  • Yong Liu 0007
  • Jianye Hao
  • Xiaotian Hao
  • Yujing Hu
  • Yingfeng Chen
  • Changjie Fan

In multiagent systems (MASs), each agent makes individual decisions but all of them contribute globally to the system evolution. Learning in MASs is difficult since each agent's selection of actions must take place in the presence of other co-learning agents. Moreover, the environmental stochasticity and uncertainties increase exponentially with the increase in the number of agents. Previous works borrow various multiagent coordination mechanisms into deep learning architecture to facilitate multiagent coordination. However, none of them explicitly consider action semantics between agents that different actions have different influences on other agents. In this paper, we propose a novel network architecture, named Action Semantics Network (ASN), that explicitly represents such action semantics between agents. ASN characterizes different actions' influence on other agents using neural networks based on the action semantics between them. ASN can be easily combined with existing deep reinforcement learning (DRL) algorithms to boost their performance. Experimental results on StarCraft II micromanagement and Neural MMO show ASN significantly improves the performance of state-of-the-art DRL approaches compared with several network architectures.

AAAI Conference 2020 Conference Paper

Continuous Multiagent Control Using Collective Behavior Entropy for Large-Scale Home Energy Management

  • Jianwen Sun
  • Yan Zheng
  • Jianye Hao
  • Zhaopeng Meng
  • Yang Liu

With the increasing popularity of electric vehicles, distributed energy generation and storage facilities in smart grid systems, an efficient Demand-Side Management (DSM) is urgent for energy savings and peak loads reduction. Traditional DSM works focusing on optimizing the energy activities for a single household can not scale up to large-scale home energy management problems. Multi-agent Deep Reinforcement Learning (MA-DRL) shows a potential way to solve the problem of scalability, where modern homes interact together to reduce energy consumers consumption while striking a balance between energy cost and peak loads reduction. However, it is difficult to solve such an environment with the non-stationarity, and existing MA-DRL approaches cannot effectively give incentives for expected group behavior. In this paper, we propose a collective MA-DRL algorithm with continuous action space to provide fine-grained control on a large scale microgrid. To mitigate the non-stationarity of the microgrid environment, a novel predictive model is proposed to measure the collective market behavior. Besides, a collective behavior entropy is introduced to reduce the high peak loads incurred by the collective behaviors of all householders in the smart grid. Empirical results show that our approach significantly outperforms the state-of-the-art methods regarding power cost reduction and daily peak loads optimization.

ICML Conference 2020 Conference Paper

Dynamic Knapsack Optimization Towards Efficient Multi-Channel Sequential Advertising

  • Xiaotian Hao
  • Zhaoqing Peng
  • Yi Ma 0005
  • Guan Wang
  • Junqi Jin
  • Jianye Hao
  • Shan Chen
  • Rongquan Bai

In E-commerce, advertising is essential for merchants to reach their target users. The typical objective is to maximize the advertiser’s cumulative revenue over a period of time under a budget constraint. In real applications, an advertisement (ad) usually needs to be exposed to the same user multiple times until the user finally contributes revenue (e. g. , places an order). However, existing advertising systems mainly focus on the immediate revenue with single ad exposures, ignoring the contribution of each exposure to the final conversion, thus usually falls into suboptimal solutions. In this paper, we formulate the sequential advertising strategy optimization as a dynamic knapsack problem. We propose a theoretically guaranteed bilevel optimization framework, which significantly reduces the solution space of the original optimization space while ensuring the solution quality. To improve the exploration efficiency of reinforcement learning, we also devise an effective action space reduction approach. Extensive offline and online experiments show the superior performance of our approaches over state-of-the-art baselines in terms of cumulative revenue.

IJCAI Conference 2020 Conference Paper

Efficient Deep Reinforcement Learning via Adaptive Policy Transfer

  • Tianpei Yang
  • Jianye Hao
  • Zhaopeng Meng
  • Zongzhang Zhang
  • Yujing Hu
  • Yingfeng Chen
  • Changjie Fan
  • Weixun Wang

Transfer learning has shown great potential to accelerate Reinforcement Learning (RL) by leveraging prior knowledge from past learned policies of relevant tasks. Existing approaches either transfer previous knowledge by explicitly computing similarities between tasks or select appropriate source policies to provide guided explorations. However, how to directly optimize the target policy by alternatively utilizing knowledge from appropriate source policies without explicitly measuring the similarities is currently missing. In this paper, we propose a novel Policy Transfer Framework (PTF) by taking advantage of this idea. PTF learns when and which source policy is the best to reuse for the target policy and when to terminate it by modeling multi-policy transfer as an option learning problem. PTF can be easily combined with existing DRL methods and experimental results show it significantly accelerates RL and surpasses state-of-the-art policy transfer methods in terms of learning efficiency and final performance in both discrete and continuous action spaces.

JAAMAS Journal 2020 Journal Article

Efficient policy detecting and reusing for non-stationarity in Markov games

  • Yan Zheng
  • Jianye Hao
  • Changjie Fan

Abstract One challenging problem in multiagent systems is to cooperate or compete with non-stationary agents that change behavior from time to time. An agent in such a non-stationary environment is usually supposed to be able to quickly detect the other agents’ policy during online interaction, and then adapt its own policy accordingly. This article studies efficient policy detecting and reusing techniques when playing against non-stationary agents in cooperative or competitive Markov games. We propose a new deep Bayesian policy reuse algorithm, a. k. a. DPN-BPR+, by extending the recent BPR+ algorithm with a neural network as the value-function approximator. To detect policy accurately, we propose the rectified belief model taking advantage of the opponent model to infer the other agents’ policy from reward signals and its behavior. Instead of directly storing individual policies as BPR+, we introduce distilled policy network that serves as the policy library, and policy distillation to achieve efficient online policy learning and reuse. DPN-BPR+ inherits all the advantages of BPR+. In experiments, we evaluate DPN-BPR+ in terms of detection accuracy, cumulative reward and speed of convergence in four complex Markov games with raw visual inputs, including two cooperative games and two competitive games. Empirical results show that our proposed DPN-BPR+ approach has better performance than existing algorithms in all these Markov games.

AAAI Conference 2020 Conference Paper

From Few to More: Large-Scale Dynamic Multiagent Curriculum Learning

  • Weixun Wang
  • Tianpei Yang
  • Yong Liu
  • Jianye Hao
  • Xiaotian Hao
  • Yujing Hu
  • Yingfeng Chen
  • Changjie Fan

A lot of efforts have been devoted to investigating how agents can learn effectively and achieve coordination in multiagent systems. However, it is still challenging in large-scale multiagent settings due to the complex dynamics between the environment and agents and the explosion of state-action space. In this paper, we design a novel Dynamic Multiagent Curriculum Learning (DyMA-CL) to solve large-scale problems by starting from learning on a multiagent scenario with a small size and progressively increasing the number of agents. We propose three transfer mechanisms across curricula to accelerate the learning process. Moreover, due to the fact that the state dimension varies across curricula, and existing network structures cannot be applied in such a transfer setting since their network input sizes are fixed. Therefore, we design a novel network structure called Dynamic Agent-number Network (DyAN) to handle the dynamic size of the network input. Experimental results show that DyMA-CL using DyAN greatly improves the performance of large-scale multiagent learning compared with state-of-the-art deep reinforcement learning approaches. We also investigate the influence of three transfer mechanisms across curricula through extensive simulations.

IJCAI Conference 2020 Conference Paper

Generating Behavior-Diverse Game AIs with Evolutionary Multi-Objective Deep Reinforcement Learning

  • Ruimin Shen
  • Yan Zheng
  • Jianye Hao
  • Zhaopeng Meng
  • Yingfeng Chen
  • Changjie Fan
  • Yang Liu

Generating diverse behaviors for game artificial intelligence (Game AI) has been long recognized as a challenging task in the game industry. Designing a Game AI with a satisfying behavioral characteristic (style) heavily depends on the domain knowledge and is hard to achieve manually. Deep reinforcement learning sheds light on advancing the automatic Game AI design. However, most of them focus on creating a superhuman Game AI, ignoring the importance of behavioral diversity in games. To bridge the gap, we introduce a new framework, named EMOGI, which can automatically generate desirable styles with almost no domain knowledge. More importantly, EMOGI succeeds in creating a range of diverse styles, providing behavior-diverse Game AIs. Evaluations on the Atari and real commercial games indicate that, compared to existing algorithms, EMOGI performs better in generating diverse behaviors and significantly improves the efficiency of Game AI design.

IJCAI Conference 2020 Conference Paper

KoGuN: Accelerating Deep Reinforcement Learning via Integrating Human Suboptimal Knowledge

  • Peng Zhang
  • Jianye Hao
  • Weixun Wang
  • Hongyao Tang
  • Yi Ma
  • Yihai Duan
  • Yan Zheng

Reinforcement learning agents usually learn from scratch, which requires a large number of interactions with the environment. This is quite different from the learning process of human. When faced with a new task, human naturally have the common sense and use the prior knowledge to derive an initial policy and guide the learning process afterwards. Although the prior knowledge may be not fully applicable to the new task, the learning process is significantly sped up since the initial policy ensures a quick-start of learning and intermediate guidance allows to avoid unnecessary exploration. Taking this inspiration, we propose knowledge guided policy network (KoGuN), a novel framework that combines human prior suboptimal knowledge with reinforcement learning. Our framework consists of a fuzzy rule controller to represent human knowledge and a refine module to finetune suboptimal prior knowledge. The proposed framework is end-to-end and can be combined with existing policy-based reinforcement learning algorithm. We conduct experiments on several control tasks. The empirical results show that our approach, which combines suboptimal human knowledge and RL, achieves significant improvement on learning efficiency of flat RL algorithms, even with very low-performance human prior knowledge.

IJCAI Conference 2020 Conference Paper

Learning to Accelerate Heuristic Searching for Large-Scale Maximum Weighted b-Matching Problems in Online Advertising

  • Xiaotian Hao
  • Junqi Jin
  • Jianye Hao
  • Jin Li
  • Weixun Wang
  • Yi Ma
  • Zhenzhe Zheng
  • Han Li

Bipartite b-matching is fundamental in algorithm design, and has been widely applied into diverse applications, such as economic markets, labor markets, etc. These practical problems usually exhibit two distinct features: large-scale and dynamic, which requires the matching algorithm to be repeatedly executed at regular intervals. However, existing exact and approximate algorithms usually fail in such settings due to either requiring intolerable running time or too much computation resource. To address this issue, based on a key observation that the matching instances vary not too much, we propose NeuSearcher which leverage the knowledge learned from previously instances to solve new problem instances. Specifically, we design a multichannel graph neural network to predict the threshold of the matched edges, by which the search region could be significantly reduced. We further propose a parallel heuristic search algorithm to iteratively improve the solution quality until convergence. Experiments on both open and industrial datasets demonstrate that NeuSearcher can speed up 2 to 3 times while achieving exactly the same matching solution compared with the state-of-the-art approximation approaches.

NeurIPS Conference 2020 Conference Paper

Learning to Utilize Shaping Rewards: A New Approach of Reward Shaping

  • Yujing Hu
  • Weixun Wang
  • Hangtian Jia
  • Yixiang Wang
  • Yingfeng Chen
  • Jianye Hao
  • Feng Wu
  • Changjie Fan

Reward shaping is an effective technique for incorporating domain knowledge into reinforcement learning (RL). Existing approaches such as potential-based reward shaping normally make full use of a given shaping reward function. However, since the transformation of human knowledge into numeric reward values is often imperfect due to reasons such as human cognitive bias, completely utilizing the shaping reward function may fail to improve the performance of RL algorithms. In this paper, we consider the problem of adaptively utilizing a given shaping reward function. We formulate the utilization of shaping rewards as a bi-level optimization problem, where the lower level is to optimize policy using the shaping rewards and the upper level is to optimize a parameterized shaping weight function for true reward maximization. We formally derive the gradient of the expected true reward with respect to the shaping weight function parameters and accordingly propose three learning algorithms based on different assumptions. Experiments in sparse-reward cartpole and MuJoCo environments show that our algorithms can fully exploit beneficial shaping rewards, and meanwhile ignore unbeneficial shaping rewards or even transform them into beneficial ones.

AAAI Conference 2020 Conference Paper

Multi-Agent Game Abstraction via Graph Attention Neural Network

  • Yong Liu
  • Weixun Wang
  • Yujing Hu
  • Jianye Hao
  • Xingguo Chen
  • Yang Gao

In large-scale multi-agent systems, the large number of agents and complex game relationship cause great difficulty for policy learning. Therefore, simplifying the learning process is an important research issue. In many multi-agent systems, the interactions between agents often happen locally, which means that agents neither need to coordinate with all other agents nor need to coordinate with others all the time. Traditional methods attempt to use pre-defined rules to capture the interaction relationship between agents. However, the methods cannot be directly used in a large-scale environment due to the difficulty of transforming the complex interactions between agents into rules. In this paper, we model the relationship between agents by a complete graph and propose a novel game abstraction mechanism based on two-stage attention network (G2ANet), which can indicate whether there is an interaction between two agents and the importance of the interaction. We integrate this detection mechanism into graph neural network-based multi-agent reinforcement learning for conducting game abstraction and propose two novel learning algorithms GA-Comm and GA-AC. We conduct experiments in Traffic Junction and Predator-Prey. The results indicate that the proposed methods can simplify the learning process and meanwhile get better asymptotic performance compared with state-of-the-art algorithms.

AAAI Conference 2020 Conference Paper

Neighborhood Cognition Consistent Multi-Agent Reinforcement Learning

  • Hangyu Mao
  • Wulong Liu
  • Jianye Hao
  • Jun Luo
  • Dong Li
  • Zhengchao Zhang
  • Jun Wang
  • Zhen Xiao

Social psychology and real experiences show that cognitive consistency plays an important role to keep human society in order: if people have a more consistent cognition about their environments, they are more likely to achieve better cooperation. Meanwhile, only cognitive consistency within a neighborhood matters because humans only interact directly with their neighbors. Inspired by these observations, we take the first step to introduce neighborhood cognitive consistency (NCC) into multi-agent reinforcement learning (MARL). Our NCC design is quite general and can be easily combined with existing MARL methods. As examples, we propose neighborhood cognition consistent deep Q-learning and Actor-Critic to facilitate large-scale multi-agent cooperations. Extensive experiments on several challenging tasks (i. e. , packet routing, wifi configuration and Google football player control) justify the superior performance of our methods compared with state-of-the-art MARL approaches.

ICML Conference 2020 Conference Paper

Q-value Path Decomposition for Deep Multiagent Reinforcement Learning

  • Yaodong Yang 0002
  • Jianye Hao
  • Guangyong Chen
  • Hongyao Tang
  • Yingfeng Chen
  • Yujing Hu
  • Changjie Fan
  • Zhongyu Wei

Recently, deep multiagent reinforcement learning (MARL) has become a highly active research area as many real-world problems can be inherently viewed as multiagent systems. A particularly interesting and widely applicable class of problems is the partially observable cooperative multiagent setting, in which a team of agents learns to coordinate their behaviors conditioning on their private observations and commonly shared global reward signals. One natural solution is to resort to the centralized training and decentralized execution paradigm and during centralized training, one key challenge is the multiagent credit assignment: how to allocate the global rewards for individual agent policies for better coordination towards maximizing system-level’s benefits. In this paper, we propose a new method called Q-value Path Decomposition (QPD) to decompose the system’s global Q-values into individual agents’ Q-values. Unlike previous works which restrict the representation relation of the individual Q-values and the global one, we leverage the integrated gradient attribution technique into deep MARL to directly decompose global Q-values along trajectory paths to assign credits for agents. We evaluate QPD on the challenging StarCraft II micromanagement tasks and show that QPD achieves the state-of-the-art performance in both homogeneous and heterogeneous multiagent scenarios compared with existing cooperative MARL algorithms.

IJCAI Conference 2020 Conference Paper

Triple-GAIL: A Multi-Modal Imitation Learning Framework with Generative Adversarial Nets

  • Cong Fei
  • Bin Wang
  • Yuzheng Zhuang
  • Zongzhang Zhang
  • Jianye Hao
  • Hongbo Zhang
  • Xuewu Ji
  • Wulong Liu

Generative adversarial imitation learning (GAIL) has shown promising results by taking advantage of generative adversarial nets, especially in the field of robot learning. However, the requirement of isolated single modal demonstrations limits the scalability of the approach to real world scenarios such as autonomous vehicles' demand for a proper understanding of human drivers' behavior. In this paper, we propose a novel multi-modal GAIL framework, named Triple-GAIL, that is able to learn skill selection and imitation jointly from both expert demonstrations and continuously generated experiences with data augmentation purpose by introducing an auxiliary selector. We provide theoretical guarantees on the convergence to optima for both of the generator and the selector respectively. Experiments on real driver trajectories and real-time strategy game datasets demonstrate that Triple-GAIL can better fit multi-modal behaviors close to the demonstrators and outperforms state-of-the-art methods.

AAAI Conference 2019 Short Paper

An Optimal Rewiring Strategy for Cooperative Multiagent Social Learning

  • Hongyao Tang
  • Jianye Hao
  • Li Wang
  • Tim Baarslag
  • Zan Wang

Multiagent coordination in cooperative multiagent systems (MASs) has been widely studied in both fixed-agent repeated interaction setting and static social learning framework. However, two aspects of dynamics in real-world MASs are currently missing. First, the network topologies can dynamically change during the course of interaction. Second, the interaction utilities between each pair of agents may not be identical and not known as a prior. Both issues mentioned above increase the difficulty of coordination. In this paper, we consider the multiagent social learning in a dynamic environment in which agents can alter their connections and interact with randomly chosen neighbors with unknown utilities beforehand. We propose an optimal rewiring strategy to select most beneficial peers to maximize the accumulated payoffs in long-run interactions. We empirically demonstrate the effects of our approach in large-scale MASs.

AAMAS Conference 2019 Conference Paper

An Optimal Rewiring Strategy for Cooperative Multiagent Social Learning

  • Hongyao Tang
  • Jianye Hao
  • Li Wang
  • Zan Wang
  • Tim Baarslag

Multiagent coordination is a key problem in cooperative multiagent systems (MASs). It has been widely studied in both fixed-agent repeated interaction setting and static social learning framework. However, two aspects of dynamics in real-world MASs are currently neglected. First, the network topologies can change during the course of interaction dynamically. Second, the interaction utilities can be different among each pair of agents and usually unknown before interaction. Both issues mentioned above increase the difficulty of coordination. In this paper, we consider the multiagent social learning in a dynamic environment in which agents can alter their connections and interact with randomly chosen neighbors with unknown utilities beforehand. We propose an optimal rewiring strategy to select most beneficial peers to maximize the accumulated payoffs in long-run interactions. We empirically demonstrate the effects of our approach in a variety of large-scale MASs.

AAMAS Conference 2019 Conference Paper

Automatic Feature Engineering by Deep Reinforcement Learning

  • Jianyu Zhang
  • Jianye Hao
  • Françoise Fogelman-Soulié
  • Zan Wang

We present a framework called Learning Automatic Feature Engineering Machine (LAFEM), which formalizes the Feature Engineering (FE) problem as an optimization problem over a Heterogeneous Transformation Graph (HTG). We propose a Deep Q-learning on HTG to support efficient learning of fine-grained and generalized FE policies that can transfer knowledge of engineering "good" features from a collection of datasets to other unseen datasets.

AAMAS Conference 2019 Conference Paper

Bayes-ToMoP: A Fast Detection and Best Response Algorithm Towards Sophisticated Opponents

  • Tianpei Yang
  • Jianye Hao
  • Zhaopeng Meng
  • Yan Zheng
  • Chongjie Zhang
  • Ze Zheng

Multiagent algorithms often aim to accurately predict the behaviors of other agents and find a best response accordingly. Previous works usually assume an opponent uses a stationary strategy or randomly switches among several stationary ones. However, an opponent may exhibit more sophisticated behaviors by adopting more advanced reasoning strategies, e. g. , using a Bayesian reasoning strategy. This paper proposes a novel approach called Bayes-ToMoP which can efficiently detect the strategy of opponents using either stationary or higher-level reasoning strategies. Bayes-ToMoP also supports the detection of previously unseen policies and learning a best-response policy accordingly. We also propose a deep version of Bayes-ToMoP by extending Bayes-ToMoP with DRL techniques. Experimental results show both Bayes-ToMoP and deep Bayes-ToMoP outperform the state-of-the-art approaches when faced with different types of opponents in two-agent competitive games.

IJCAI Conference 2019 Conference Paper

Building Personalized Simulator for Interactive Search

  • Qianlong Liu
  • Baoliang Cui
  • Zhongyu Wei
  • Baolin Peng
  • Haikuan Huang
  • Hongbo Deng
  • Jianye Hao
  • Xuanjing Huang

Interactive search, where a set of tags is recommended to users together with search results at each turn, is an effective way to guide users to identify their information need. It is a classical sequential decision problem and the reinforcement learning based agent can be introduced as a solution. The training of the agent can be divided into two stages, i. e. , offline and online. Existing reinforcement learning based systems tend to perform the offline training in a supervised way based on historical labeled data while the online training is performed via reinforcement learning algorithms based on interactions with real users. The mis-match between online and offline training leads to a cold-start problem for the online usage of the agent. To address this issue, we propose to employ a simulator to mimic the environment for the offline training of the agent. Users' profiles are considered to build a personalized simulator, besides, model-based approach is used to train the simulator and is able to use the data efficiently. Experimental results based on real-world dataset demonstrate the effectiveness of our agent and personalized simulator.

IJCAI Conference 2019 Conference Paper

Deep Multi-Agent Reinforcement Learning with Discrete-Continuous Hybrid Action Spaces

  • Haotian Fu
  • Hongyao Tang
  • Jianye Hao
  • Zihan Lei
  • Yingfeng Chen
  • Changjie Fan

Deep Reinforcement Learning (DRL) has been applied to address a variety of cooperative multi-agent problems with either discrete action spaces or continuous action spaces. However, to the best of our knowledge, no previous work has ever succeeded in applying DRL to multi-agent problems with discrete-continuous hybrid (or parameterized) action spaces which is very common in practice. Our work fills this gap by proposing two novel algorithms: Deep Multi-Agent Parameterized Q-Networks (Deep MAPQN) and Deep Multi-Agent Hierarchical Hybrid Q-Networks (Deep MAHHQN). We follow the centralized training but decentralized execution paradigm: different levels of communication between different agents are used to facilitate the training process, while each agent executes its policy independently based on local observations during execution. Our empirical results on several challenging tasks (simulated RoboCup Soccer and game Ghost Story) show that both Deep MAPQN and Deep MAHHQN are effective and significantly outperform existing independent deep parameterized Q-learning method.

IJCAI Conference 2019 Conference Paper

Explicitly Coordinated Policy Iteration

  • Yujing Hu
  • Yingfeng Chen
  • Changjie Fan
  • Jianye Hao

Coordination on an optimal policy between independent learners in fully cooperative stochastic games is difficult due to problems such as relative overgeneralization and miscoordination. Most state-of-the-art algorithms apply fusion heuristics on agents' optimistic and average rewards, by which coordination between agents can be achieved implicitly. However, such implicit coordination faces practical issues such as tedious parameter-tuning in real world applications. The lack of an explicit coordination mechanism may also lead to a low likelihood of coordination in problems with multiple optimal policies. Based on the necessary conditions of an optimal policy, we propose the explicitly coordinated policy iteration (EXCEL) algorithm which always forces agents to coordinate by comparing the agents' separated optimistic and average value functions. We also propose three solutions for deep reinforcement learning extensions of EXCEL. Extensive experiments in matrix games (from 2-agent 2-action games to 5-agent 20-action games) and stochastic games (from 2-agent games to 5-agent games) show that EXCEL has better performance than the state-of-the-art algorithms (such as faster convergence and better coordination).

AAMAS Conference 2019 Conference Paper

Independent Generative Adversarial Self-Imitation Learning in Cooperative Multiagent Systems

  • Xiaotian Hao
  • Weixun Wang
  • Jianye Hao
  • Yaodong Yang

Many tasks in practice require the collaboration of multiple agents through reinforcement learning. In general, cooperative multiagent reinforcement learning algorithms can be classified into two paradigms: Joint Action Learners (JALs) and Independent Learners (ILs). In many practical applications, agents are unable to observe other agents’ actions and rewards, making JALs inapplicable. In this work, we focus on independent learning paradigm in which each agent makes decisions based on its local observations only. However, learning is challenging in independent settings due to the local viewpoints of all agents, which perceive the world as a non-stationary environment due to the concurrently exploring teammates. In this paper, we propose a novel framework called Independent Generative Adversarial Self-Imitation Learning (IGASIL) to address the coordination problems in fully cooperative multiagent environments. To the best of our knowledge, we are the first to combine self-imitation learning with generative adversarial imitation learning (GAIL) and apply it to cooperative multiagent systems. Besides, we put forward a Sub-Curriculum Experience Replay mechanism to pick out the past beneficial experiences as much as possible and accelerate the self-imitation learning process. Evaluations conducted in the testbed of StarCraft unit micromanagement and a commonly adopted benchmark show that our IGASIL produces state-of-the-art results and even outperforms JALs in terms of both convergence speed and final performance.

IJCAI Conference 2019 Conference Paper

Large-Scale Home Energy Management Using Entropy-Based Collective Multiagent Deep Reinforcement Learning Framework

  • Yaodong Yang
  • Jianye Hao
  • Yan Zheng
  • Chao Yu

Smart grids are contributing to the demand-side management by integrating electronic equipment, distributed energy generation and storage and advanced meters and controllers. With the increasing adoption of electric vehicles and distributed energy generation and storage systems, residential energy management is drawing more and more attention, which is regarded as being critical to demand-supply balancing and peak load reduction. In this paper, we focus on a microgrid scenario in which modern homes interact together under a large-scale setting to better optimize their electricity cost. We first make households form a group with an economic stimulus. Then we formulate the energy expense optimization problem of the household community as a multi-agent coordination problem and present an Entropy-Based Collective Multiagent Deep Reinforcement Learning (EB-C-MADRL) framework to address it. Experiments with various real-world data demonstrate that EB-C-MADRL can reduce both the long-term group power consumption cost and daily peak demand effectively compared with existing approaches.

AAMAS Conference 2019 Conference Paper

Large-Scale Home Energy Management Using Entropy-Based Collective Multiagent Reinforcement Learning Framework

  • Yaodong Yang
  • Jianye Hao
  • Yan Zheng
  • Xiaotian Hao
  • Bofeng Fu

Smart grids are contributing to the demand-side management by integrating electronic equipment, distributed energy generation and storage, and advanced meters and controllers. With the increasing adoption of distributed energy generation and storage systems, residential energy management is drawing more and more attention, which is regarded as being critical to demand-supply balancing and peak load reduction. In this paper, we focus on a microgrid in which a large-scale modern homes interact together to optimize their electricity cost. We present an Entropy-Based Collective Multiagent Deep Reinforcement Learning (EB-C-MADRL) framework to address it. Experiments demonstrate that EB-C-MADRL can reduce both the long-term group power consumption cost and daily peak demand effectively compared with existing approaches.

AAMAS Conference 2019 Conference Paper

ONECG: Online Negotiation Environment for Coalitional Games

  • Siqi Chen
  • Yonghao Cui
  • Cong Shang
  • Jianye Hao
  • Gerhard Weiss

Coalitional games can be used to model a variety of problems in the real world. In coalitional game theory, how players form coalitions and divide payoffs is one fundamental issue to be answered. This demo presents an online negotiation environment for coalitional games (ONECG), in which coalitional negotiation can be conduced in a distributed way between people, agents, or in mixed settings via offer exchange and natural language communication. ONECG also allows con- figuration of specifications of coalitional games, and supports the rapid development of new negotiating agents through a set of well-defined APIs. This new environment is helpful to facilitate research on training human negotiation skills in coalitional games as well as the design of negotiation agents.

AAMAS Conference 2019 Conference Paper

Reinforcement Learning for Cooperative Overtaking

  • Chao Yu
  • Xin Wang
  • Jianye Hao
  • Zhanbo Feng

This paper solves the cooperative overtaking problem in autonomous driving using reinforcement learning techniques. Learning in such a situation is challenging due to vehicular mobility, which renders a continuously changing environment for each learning vehicle. Without no explicit coordination mechanisms, inefficient behaviors among vehicles might cause fatal uncoordinated outcomes. To solve this issue, we propose two basic coordination models to enable distributed learning of cooperative overtaking maneuvers in a group of vehicles. Extension mechanisms are then presented to make these models workable in more complex and realistic settings with any number of vehicles. Experiments verify that, by capturing the underlying consistency of identities or positions during vehicles’ movement, efficient coordinated behaviors can be achieved simply through vehicles’ local learning interactions.

IJCAI Conference 2019 Conference Paper

Towards Efficient Detection and Optimal Response against Sophisticated Opponents

  • Tianpei Yang
  • Jianye Hao
  • Zhaopeng Meng
  • Chongjie Zhang
  • Yan Zheng
  • Ze Zheng

Multiagent algorithms often aim to accurately predict the behaviors of other agents and find a best response accordingly. Previous works usually assume an opponent uses a stationary strategy or randomly switches among several stationary ones. However, an opponent may exhibit more sophisticated behaviors by adopting more advanced reasoning strategies, e. g. , using a Bayesian reasoning strategy. This paper proposes a novel approach called Bayes-ToMoP which can efficiently detect the strategy of opponents using either stationary or higher-level reasoning strategies. Bayes-ToMoP also supports the detection of previously unseen policies and learning a best-response policy accordingly. We provide a theoretical guarantee of the optimality on detecting the opponent's strategies. We also propose a deep version of Bayes-ToMoP by extending Bayes-ToMoP with DRL techniques. Experimental results show both Bayes-ToMoP and deep Bayes-ToMoP outperform the state-of-the-art approaches when faced with different types of opponents in two-agent competitive games.

NeurIPS Conference 2018 Conference Paper

A Deep Bayesian Policy Reuse Approach Against Non-Stationary Agents

  • Yan Zheng
  • Zhaopeng Meng
  • Jianye Hao
  • Zongzhang Zhang
  • Tianpei Yang
  • Changjie Fan

In multiagent domains, coping with non-stationary agents that change behaviors from time to time is a challenging problem, where an agent is usually required to be able to quickly detect the other agent's policy during online interaction, and then adapt its own policy accordingly. This paper studies efficient policy detecting and reusing techniques when playing against non-stationary agents in Markov games. We propose a new deep BPR+ algorithm by extending the recent BPR+ algorithm with a neural network as the value-function approximator. To detect policy accurately, we propose the \textit{rectified belief model} taking advantage of the \textit{opponent model} to infer the other agent's policy from reward signals and its behaviors. Instead of directly storing individual policies as BPR+, we introduce \textit{distilled policy network} that serves as the policy library in BPR+, using policy distillation to achieve efficient online policy learning and reuse. Deep BPR+ inherits all the advantages of BPR+ and empirically shows better performance in terms of detection accuracy, cumulative rewards and speed of convergence compared to existing algorithms in complex Markov games with raw visual inputs.

AAMAS Conference 2018 Conference Paper

Efficient Convention Emergence through Decoupled Reinforcement Social Learning with Teacher-Student Mechanism

  • Yixi Wang
  • Wenhuan Lu
  • Jianye Hao
  • Jianguo Wei
  • Ho-fung Leung

In this paper, we design reinforcement learning based (RLbased) strategies to promote convention emergence in multiagent systems (MASs) with large convention space. We apply our approaches to a language coordination problem in which agents need to coordinate on a dominant lexicon for efficient communication. By modeling each lexicon which maps each concept to a single word as a Markov strategy representation, the original single-state convention learning problem can be transformed into a multi-state multiagent coordination problem. The dynamics of lexicon evolutions during an interaction episode can be modeled as a Markov game, which allows agents to improve the action values of each concept separately and incrementally. Specifically we propose two learning strategies, multiple-Q and multiple-R, and also propose incorporating teacher-student mechanism on top of the learning strategies to accelerate lexicon convergence speed. Extensive experiments verify that our approaches outperform the state-of-the-art approaches in terms of convergence efficiency, convention quality and scalability.

AAMAS Conference 2018 Conference Paper

Recurrent Deep Multiagent Q-Learning for Autonomous Agents in Future Smart Grid

  • Yaodong Yang
  • Jianye Hao
  • Zan Wang
  • Mingyang Sun
  • Goran Strbac

The broker mechanism is widely applied to serve for interested parties to derive long-term policies to reduce costs or gain profits in smart grid. However, brokers are faced with a number of challenging problems such as balancing demand and supply from customers and competing with other coexisting brokers to maximize profits. In this paper, we develop an effective pricing strategy for brokers in local electricity retail market based on recurrent deep multiagent reinforcement learning and sequential clustering. We use real household electricity consumption data to simulate the retail market for evaluating our strategy. The experiments demonstrate the superior performance of the proposed pricing strategy and highlight the effectiveness of our reward shaping mechanism.

IJCAI Conference 2018 Conference Paper

Recurrent Deep Multiagent Q-Learning for Autonomous Brokers in Smart Grid

  • Yaodong Yang
  • Jianye Hao
  • Mingyang Sun
  • Zan Wang
  • Changjie Fan
  • Goran Strbac

The broker mechanism is widely applied to serve for interested parties to derive long-term policies in order to reduce costs or gain profits in smart grid. However, a broker is faced with a number of challenging problems such as balancing demand and supply from customers and competing with other coexisting brokers to maximize its profit. In this paper, we develop an effective pricing strategy for brokers in local electricity retail market based on recurrent deep multiagent reinforcement learning and sequential clustering. We use real household electricity consumption data to simulate the retail market for evaluating our strategy. The experiments demonstrate the superior performance of the proposed pricing strategy and highlight the effectiveness of our reward shaping mechanism.

AAMAS Conference 2018 Conference Paper

SCC-rFMQ Learning in Cooperative Markov Games with Continuous Actions

  • Chengwei Zhang
  • Xiaohong Li
  • Jianye Hao
  • Siqi Chen
  • Karl Tuyls
  • Zhiyong Feng

Although many reinforcement learning methods have been proposed for learning the optimal solutions in single-agent continuous action domains, multiagent coordination domains with continuous action have received relatively few investigations. In this paper, we propose an independent learner hierarchical method, named Sample Continuous Coordination with recursive Frequency Maximum Q-Value (SCC-rFMQ), which divides the coordination problem into two layers. The first layer samples a finite set of actions from the continuous action spaces by a sampling mechanism with variable exploratory rates, and the second layer evaluates the actions in the sampled action set and updates the policy using a multiagent reinforcement learning coordination method. By constructing coordination mechanisms at both levels, SCCrFMQ can handle coordination problems in continuous action cooperative Markov games effectively. Experimental results show that SCC-rFMQ outperforms other reinforcement learning algorithms.

AAMAS Conference 2018 Conference Paper

The Dynamics of Opinion Evolution in Gossiper-Media Model with WoLS-CALA Learning

  • Chengwei Zhang
  • Xiaohong Li
  • Jianye Hao
  • Sandip Sen
  • Wanli Xue
  • Zhiyong Feng

In social networks, media outlets such as TV, newspapers, blogs adjust their opinions to cater to the public’s interest to increase the number of followers. Meanwhile, the evolution of the public’s opinions are affected by both the media and the peers they interact with. In this work, we investigate how the interactions between mainstream media affect the dynamics of the public’s opinions in social networks. We propose a reinforcement learning framework to model the interactions between the public (aka gossipers) and the media agents. We model each gossiper as an individually rational agent, which updates its opinion using the Bounded Confidence Model (BCM). Each media agent is interested in maximizing the number of following gossipers competitively, and an adaptive WoLS-CALA (Win or Learn Slow Continuous Action Learning Automaton) algorithm is proposed to achieve that goal. We theoretically prove that WoLS-CALA can learn to Nash equilibria for two-agent games with continuous action space. Besides, the opinion dynamics of both gossipers and media are theoretically analyzed. Extensive empirical simulation reveals the opinion dynamics of our framework facilitates the consensus of opinions and confirms the theoretical analysis.

IJCAI Conference 2017 Conference Paper

Defending Against Man-In-The-Middle Attack in Repeated Games

  • Shuxin Li
  • Xiaohong Li
  • Jianye Hao
  • Bo An
  • Zhiyong Feng
  • Kangjie Chen
  • Chengwei Zhang

The Man-in-the-Middle (MITM) attack has become widespread in networks nowadays. The MITM attack would cause serious information leakage and result in tremendous loss to users. Previous work applies game theory to analyze the MITM attack-defense problem and computes the optimal defense strategy to minimize the total loss. It assumes that all defenders are cooperative and the attacker know defenders' strategies beforehand. However, each individual defender is rational and may not have the incentive to cooperate. Furthermore, the attacker can hardly know defenders' strategies ahead of schedule in practice. To this end, we assume that all defenders are self-interested and model the MITM attack-defense scenario as a simultaneous-move game. Nash equilibrium is adopted as the solution concept which is proved to be always unique. Given the impracticability of computing Nash equilibrium directly, we propose practical adaptive algorithms for the defenders and the attacker to learn towards the unique Nash equilibrium through repeated interactions. Simulation results show that the algorithms are able to converge to Nash equilibrium strategy efficiently.

TAAS Journal 2017 Journal Article

Efficient and Robust Emergence of Norms through Heuristic Collective Learning

  • Jianye Hao
  • Jun Sun
  • Guangyong Chen
  • Zan Wang
  • Chao Yu
  • Zhong Ming

In multiagent systems, social norms serves as an important technique in regulating agents’ behaviors to ensure effective coordination among agents without a centralized controlling mechanism. In such a distributed environment, it is important to investigate how a desirable social norm can be synthesized in a bottom-up manner among agents through repeated local interactions and learning techniques. In this article, we propose two novel learning strategies under the collective learning framework, collective learning EV-l and collective learning EV-g, to efficiently facilitate the emergence of social norms. Extensive simulations results show that both learning strategies can support the emergence of desirable social norms more efficiently and be applicable in a wider range of multiagent interaction scenarios compared with previous work. The influence of different topologies is investigated, which shows that the performance of all strategies is robust across different network topologies. The influences of a number of key factors (neighborhood size, actions space, population size, fixed agents and isolated subpopulations) on norm emergence performance are investigated as well.

AAAI Conference 2017 Conference Paper

Optimal Personalized Defense Strategy Against Man-In-The-Middle Attack

  • Xiaohong Li
  • Shuxin Li
  • Jianye Hao
  • Zhiyong Feng
  • Bo An

The Man-In-The-Middle (MITM) attack is one of the most common attacks employed in the network hacking. MITM attackers can successfully invoke attacks such as denial of service (DoS) and port stealing, and lead to surprisingly harmful consequences for users in terms of both financial loss and security issues. The conventional defense approaches mainly consider how to detect and eliminate those attacks or how to prevent those attacks from being launched in the first place. This paper proposes a game-theoretic defense strategy from a different perspective, which aims at minimizing the loss that the whole system sustains given that the MITM attacks are inevitable. We model the interaction between the attacker and the defender as a Stackelberg security game and adopt the Strong Stackelberg Equilibrium (SSE) as the defender’s strategy. Since the defender’s strategy space is infinite in our model, we employ a novel method to reduce the searching space of computing the optimal defense strategy. Finally, we empirically evaluate our optimal defense strategy by comparing it with non-strategic defense strategies. The results indicate that our game-theoretic defense strategy significantly outperforms other non-strategic defense strategies in terms of decreasing the total losses against MITM attacks.

EAAI Journal 2017 Journal Article

The dynamics of reinforcement social learning in networked cooperative multiagent systems

  • Jianye Hao
  • Dongping Huang
  • Yi Cai
  • Ho-fung Leung

Multiagent coordination in cooperative multiagent systems, as one of the fundamental problems in multiagent systems, and has been widely studied in the literature. In real environments, the interactions among agents are usually sparse and regulated by their underlying network structure, which, however, has received relatively few attentions in previous work. To this end, we firstly systematically investigate the multiagent coordination problems in cooperative environments under the networked social learning framework under four representative topologies. A networked social learning framework consists of a population of agents where each agent interacts with another agent randomly selected from its neighborhood in each round. Each agent updates its learning policy through repeated interactions with its neighbors via both individual learning and social learning. It is not clear a priori whether all agents are able to learn towards a consistent optimal coordination policy. Two types of learners are proposed: individual action learner and joint action learner. We evaluate the learning performances of both learners extensively in different cooperative (both single-stage and Markov) games. Besides, the influence of different factors (network topologies, different types of games, different topology parameters) is investigated and analyzed and new insights are obtained.

ECAI Conference 2016 Conference Paper

Accelerating Norm Emergence Through Hierarchical Heuristic Learning

  • Tianpei Yang
  • Zhaopeng Meng
  • Jianye Hao
  • Sandip Sen
  • Chao Yu 0004

Social norms serve as an important mechanism to regulate the behaviours of agents and to facilitate coordination among them in multiagent systems. One important research question is how a norm can rapidly emerge through repeated local interaction within agent societies under different environments when their coordination space becomes large. To address this problem, we propose a hierarchically heuristic learning strategy (HHLS) under the hierarchical social learning framework. Subordinate agents report their information to their supervisors, while supervisors can generate instructions (rules and suggestions) based on the information collected from their subordinates. Subordinate agents heuristically update their strategies based on both their own experience and the instructions from their supervisors. Extensive experiment evaluations show that HHLS can support the emergence of desirable social norms more efficiently and can be applicable in a much wider range of multiagent interaction scenarios compared with previous work. The influence of key related factors (e. g. , different topologies, population, neighbourhood and action space size, cluster size) are also investigated and new insights are obtained as well.

AAMAS Conference 2016 Conference Paper

An Adaptive Learning Framework for Efficient Emergence of Social Norms (Extended Abstract)

  • Chao Yu
  • Hongtao Lv
  • Sandip Sen
  • Jianye Hao
  • Fenghui Ren
  • Rui Liu

This paper investigates how norm emergence can be facilitated by agents’ adaptive learning behaviors. A general learning framework is proposed, in which agents can dynamically adapt their learning behaviors through social learning of their individual learning experience. Experimental results indicate that the proposed framework outperforms the static learning framework in various comparison criteria.

ECAI Conference 2016 Conference Paper

Socially-Aware Multiagent Learning: Towards Socially Optimal Outcomes

  • Xiaohong Li 0001
  • Chengwei Zhang 0001
  • Jianye Hao
  • Karl Tuyls
  • Siqi Chen 0001
  • Zhiyong Feng 0002

In multiagent systems the capability of learning is important for an agent to behave appropriately in face of unknown opponents and a dynamic environment. From the system designer's perspective, it is desirable if the agents can learn to coordinate towards socially optimal outcomes, while also avoiding being exploited by selfish opponents. To this end, we propose a novel gradient ascent based algorithm (SA-IGA) which augments the basic gradient-ascent algorithm by incorporating social awareness into the policy update process. We theoretically analyze the learning dynamics of SA-IGA using dynamical system theory, and SA-IGA is shown to have linear dynamics for a wide range of games including symmetric games. The learning dynamics of two representative games (the prisoner's dilemma game and coordination game) are analyzed in detail. Based on the idea of SA-IGA, we further propose a practical multiagent learning algorithm, called SA-PGA, based on the Q-learning update rule. Simulation results show that an SA-PGA agent can achieve higher social welfare than previous social-optimality oriented Conditional Joint Action Learner (CJAL) and also is robust against individually rational opponents by reaching Nash equilibrium solutions.

EAAI Journal 2014 Journal Article

An efficient and robust negotiating strategy in bilateral negotiations over multiple items

  • Jianye Hao
  • Songzheng Song
  • Ho-fung Leung
  • Zhong Ming

Multi-item negotiations surround our daily life and usually involve two parties that share common or conflicting interests. Effective automated negotiation techniques should enable the agents to adaptively adjust their behaviors depending on the characteristics of their negotiating partners and negotiation scenarios. This is complicated by the fact that the negotiation agents are usually unwilling to reveal their information (strategies and preferences) to avoid being exploited during negotiation. In this paper, we propose an adaptive negotiation strategy, called ABiNeS, which can make effective negotiations against different types of negotiating partners. The ABiNeS strategy employs the non-exploitation point to adaptively adjust the appropriate time to stop exploiting the negotiating partner and also predicts the optimal offer for the negotiating partner based on the reinforcement-learning based approach. Simulation results show that the ABiNeS strategy can perform more efficient exploitations against different types of negotiating partners, and thus achieve higher overall payoffs compared with the state-of-the-art strategies under negotiation tournaments. We also provide a detailed analysis of why the ABiNeS strategy can negotiate more efficiently compared with other existing state-of-the-art negotiation strategies focusing on two major components. Lastly, we propose adopting the single-agent best deviation principle to analyze the robustness of different negotiation strategies based on model checking techniques. Through our analysis, the ABiNeS strategy is shown to be very robust against other state-of-the-art strategies under different negotiation contexts.

JAAMAS Journal 2014 Journal Article

Introducing decision entrustment mechanism into repeated bilateral agent interactions to achieve social optimality

  • Jianye Hao
  • Ho-fung Leung

Abstract During multiagent interactions, robust strategies are needed to help the agents to coordinate their actions on efficient outcomes. A large body of previous work focuses on designing strategies towards the goal of Nash equilibrium under self-play, which can be extremely inefficient in many situations such as prisoner’s dilemma game. To this end, we propose an alternative solution concept, socially optimal outcome sustained by Nash equilibrium (SOSNE), which refers to those outcomes that maximize the sum of all agents’ payoffs among all the possible outcomes that can correspond to a Nash equilibrium payoff profile in the infinitely repeated games. Adopting the solution concept of SOSNE guarantees that the system-level performance can be maximized provided that no agent will sacrifice its individual profits. On the other hand, apart from performing well under self-play, a good strategy should also be able to well respond against those opponents adopting different strategies as much as possible. To this end, we consider a particular class of rational opponents and we target at influencing those opponents to coordinate on SOSNE outcomes. We propose a novel learning strategy TaFSO which combines the characteristics of both teacher and follower strategies to effectively influence the opponent’s behavior towards SOSNE outcomes by exploiting their limitations. Extensive simulations show that our strategy TaFSO achieves better performance in terms of average payoffs obtained than previous work under both self-play and against the same class of rational opponents.

TAAS Journal 2014 Journal Article

Multiagent Reinforcement Social Learning toward Coordination in Cooperative Multiagent Systems

  • Jianye Hao
  • Ho-fung Leung
  • Zhong Ming

Most previous works on coordination in cooperative multiagent systems study the problem of how two (or more) players can coordinate on Pareto-optimal Nash equilibrium(s) through fixed and repeated interactions in the context of cooperative games. However, in practical complex environments, the interactions between agents can be sparse, and each agent's interacting partners may change frequently and randomly. To this end, we investigate the multiagent coordination problems in cooperative environments under a social learning framework. We consider a large population of agents where each agent interacts with another agent randomly chosen from the population in each round. Each agent learns its policy through repeated interactions with the rest of the agents via social learning. It is not clear a priori if all agents can learn a consistent optimal coordination policy in such a situation. We distinguish two different types of learners depending on the amount of information each agent can perceive: individual action learner and joint action learner. The learning performance of both types of learners is evaluated under a number of challenging deterministic and stochastic cooperative games, and the influence of the information sharing degree on the learning performance also is investigated—a key difference from the learning framework involving repeated interactions among fixed agents.

ECAI Conference 2014 Conference Paper

Spatial evolutionary game-theoretic perspective on agent-based complex negotiations

  • Siqi Chen 0001
  • Jianye Hao
  • Gerhard Weiß 0001
  • Karl Tuyls
  • Ho-fung Leung

The complexity of automated negotiation in a multi-issue, incomplete-information and continuous-time environment poses severe challenges, and in recent years many strategies have been proposed in response to this challenge. For the traditional evolution, strategies are studied in games assuming that "globally" negotiates with all other participates. This evaluation, however, is not suited for negotiation settings that are primarily characterized by "local" interactions among the participating agents, that is, settings in which each of possibly many participating agents negotiates only with its local neighbors rather than all other agents. A new class of negotiation games is therefore introduced that take negotiation locality (hence spatial information about the agents) into consideration. It is shown how spatial evolutionary game theory can be used to interpret bilateral negotiation results among state-of-the-art strategies.

TAAS Journal 2013 Journal Article

Achieving Socially Optimal Outcomes in Multiagent Systems with Reinforcement Social Learning

  • Jianye Hao
  • Ho-fung Leung

In multiagent systems, social optimality is a desirable goal to achieve in terms of maximizing the global efficiency of the system. We study the problem of coordinating on socially optimal outcomes among a population of agents, in which each agent randomly interacts with another agent from the population each round. Previous work [Hales and Edmonds 2003; Matlock and Sen 2007, 2009] mainly resorts to modifying the interaction protocol from random interaction to tag-based interactions and only focus on the case of symmetric games. Besides, in previous work the agents’ decision making processes are usually based on evolutionary learning, which usually results in high communication cost and high deviation on the coordination rate. To solve these problems, we propose an alternative social learning framework with two major contributions as follows. First, we introduce the observation mechanism to reduce the amount of communication required among agents. Second, we propose that the agents’ learning strategies should be based on reinforcement learning technique instead of evolutionary learning. Each agent explicitly keeps the record of its current state in its learning strategy, and learn its optimal policy for each state independently. In this way, the learning performance is much more stable and also it is suitable for both symmetric and asymmetric games. The performance of this social learning framework is extensively evaluated under the testbed of two-player general-sum games comparing with previous work [Hao and Leung 2011; Matlock and Sen 2007]. The influences of different factors on the learning performance of the social learning framework are investigated as well.

AAMAS Conference 2013 Conference Paper

Reinforcement Social Learning of Coordination in Cooperative Multiagent Systems

  • Jianye Hao
  • Ho-fung Leung

Coordination in cooperative multiagent systems is an important problem and has received a lot of attention in multiagent learning literature. Most of previous works study the problem of how two (or more) players can coordinate on Pareto-optimal Nash equilibrium(s) through fixed and repeated interactions in the context of cooperative games. However, in practical complex environments, the interactions between agents can be sparse, and each agent’s interacting partners may change frequently and randomly. To this end, in this paper, we investigate the multiagent coordination problems in cooperative environments under the social learning framework, in which there exists a large population of agents and each agent interacts with another agent randomly in each round. Each agent learns its policy through repeated interactions with the rest of agents via social learning. We distinguish two different types of learners depending on the amount of information each agent can perceive: individual action learner and joint action learner. The learning performance of both types of learners are evaluated under a number of challenging deterministic and stochastic cooperative games.

IJCAI Conference 2013 Conference Paper

The Dynamics of Reinforcement Social Learning in Cooperative Multiagent Systems

  • Jianye Hao
  • Ho-fung Leung

Coordination in cooperative multiagent systems is an important problem in multiagent learning literature. In practical complex environments, the interactions between agents can be sparse, and each agent’s interacting partners may change frequently and randomly. To this end, we investigate the multiagent coordination problems in cooperative environments under the social learning framework. We consider a large population of agents where each agent interacts with another agent randomly chosen from the population in each round. Each agent learns its policy through repeated interactions with the rest of agents via social learning. It is not clear a priori if all agents can learn a consistent optimal coordination policy in such a situation. We distinguish two types of learners: individual action learner and joint action learner. The learning performance of both learners are evaluated under a number of challenging cooperative games, and the influence of the information sharing degree on the learning performance is investigated as well.

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