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Aparna Taneja

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22 papers
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22

AAMAS Conference 2025 Conference Paper

Bayesian Collaborative Bandits with Thompson Sampling for Improved Outreach in Maternal Health

  • Arpan Dasgupta
  • Gagan Jain
  • Arun Suggala
  • Karthikeyan Shanmugam
  • Milind Tambe
  • Aparna Taneja

Mobile health (mHealth) programs face a critical challenge in optimizing the timing of automated health information calls to beneficiaries. This challenge has been formulated as a collaborative multiarmed bandit problem, requiring online learning of a low-rank reward matrix. Existing solutions often rely on heuristic combinations of offline matrix completion and exploration strategies. In this work, we propose a principled Bayesian approach using Thompson Sampling for this collaborative bandit problem. Our method leverages prior information through efficient Gibbs sampling for posterior inference over the low-rank matrix factors, enabling faster convergence. We demonstrate significant improvements over stateof-the-art baselines on a real-world dataset from the world’s largest maternal mHealth program. Our approach achieves a 16% reduction in the number of calls compared to existing methods and a 47% reduction compared to the deployed random policy. This efficiency gain translates to a potential increase in program capacity by 0. 5 − 1. 4 million beneficiaries, granting them access to vital antenatal and post-natal care information. Furthermore, we observe a 7% and 29% improvement in beneficiary retention (an extremely hard metric to impact) compared to state-of-the-art and deployed baselines, respectively. Synthetic simulations further demonstrate the superiority of our approach, particularly in low-data regimes and in effectively utilizing prior information. We also provide a theoretical analysis of our algorithm in a special setting using Eluder dimension.

ECAI Conference 2025 Conference Paper

Beyond Listenership: AI-Predicted Interventions Drive Improvements in Maternal Health Behaviours

  • Arpan Dasgupta
  • Sarvesh Gharat
  • Neha Madhiwalla
  • Aparna Hegde
  • Milind Tambe
  • Aparna Taneja

Automated voice calls with health information are a proven method for disseminating maternal and child health information among beneficiaries and are deployed in several programs around the world. However, these programs often suffer from beneficiary dropoffs and poor engagement. In previous work, through real-world trials, we showed that an AI model, specifically a restless bandit model, could identify beneficiaries who would benefit most from live service call interventions, preventing dropoffs and boosting engagement. However, one key question has remained open so far: does such improved listenership via AI-targeted interventions translate into beneficiaries’ improved knowledge and health behaviors? We present a first study that shows not only listenership improvements due to AI interventions, but also simultaneously links these improvements to health behavior changes. Specifically, we demonstrate that AI-scheduled interventions, which enhance listenership, lead to statistically significant improvements in beneficiaries’ health behaviors such as taking iron or calcium supplements in the postnatal period, as well as understanding of critical health topics during pregnancy and infancy. This underscores the potential of AI to drive meaningful improvements in maternal and child health.

AAAI Conference 2025 Conference Paper

Context in Public Health for Underserved Communities: A Bayesian Approach to Online Restless Bandits

  • Biyonka Liang
  • Lily Xu
  • Aparna Taneja
  • Milind Tambe
  • Lucas Janson

Public health programs often provide interventions to encourage program adherence, and effectively allocating interventions is vital for producing the greatest overall health outcomes, especially in underserved communities where resources are limited. Such resource allocation problems are often modeled as restless multi-armed bandits (RMABs) with unknown underlying transition dynamics, hence requiring online reinforcement learning (RL). We present Bayesian Learning for Contextual RMABs (BCoR), an online RL approach for RMABs that novelly combines techniques in Bayesian modeling with Thompson sampling to flexibly model the complex RMAB settings present in public health program adherence problems, namely context and non-stationarity. BCoR's key strength is the ability to leverage shared information within and between arms to learn the unknown RMAB transition dynamics quickly in intervention-scarce settings with relatively short time horizons, which is common in public health applications. Empirically, BCoR achieves substantially higher finite-sample performance over a range of experimental settings, including a setting using real-world adherence data that was developed in collaboration with ARMMAN, an NGO in India which runs a large-scale maternal mHealth program, showcasing BCoR practical utility and potential for real-world deployment.

AAAI Conference 2025 Conference Paper

Evaluating Index-based Treatment Allocation in Underresourced Communities

  • Niclas Boehmer
  • Yash Nair
  • Sanket Shah
  • Lucas Janson
  • Aparna Taneja
  • Milind Tambe

In many applications of AI for Social Impact (e.g., when allocating spots in support programs for underserved communities), resources are scarce and an allocation policy is needed to decide who receives a resource. Before being deployed at scale, a rigorous evaluation of an AI-powered allocation policy is vital. In this paper, we introduce the methods necessary to evaluate index-based allocation policies, which allocate a limited number of resources to those who need them the most. Such policies create dependencies between agents, rendering standard statistical tests invalid and ineffective. Addressing the arising practical and technical challenges, we describe an efficient estimator and methods for drawing valid statistical conclusions. Our extensive experiments validate our methodology in practical settings while also showcasing its statistical power. We conclude by proposing and empirically verifying extensions of our methodology that enable us to reevaluate a past randomized control trial conducted with 10000 beneficiaries for a mHealth program for pregnant women. Our new methodology allows us to draw previously invisible conclusions when comparing two different ML allocation policies.

AAAI Conference 2025 Conference Paper

The Bandit Whisperer: Communication Learning for Restless Bandits

  • Yunfan Zhao
  • Tonghan Wang
  • Dheeraj Mysore Nagaraj
  • Aparna Taneja
  • Milind Tambe

Applying Reinforcement Learning (RL) to Restless Multi-Arm Bandits (RMABs) offers a promising avenue for addressing allocation problems with resource constraints and temporal dynamics. However, classic RMAB models largely overlook the challenges of (systematic) data errors - a common occurrence in real-world scenarios due to factors like varying data collection protocols and intentional noise for differential privacy. We demonstrate that conventional RL algorithms used to train RMABs can struggle to perform well in such settings. To solve this problem, we propose the first communication learning approach in RMABs, where we study which arms, when involved in communication, are most effective in mitigating the influence of such systematic data errors. In our setup, the arms receive Q-function parameters from similar arms as messages to guide behavioral policies, steering Q-function updates. We learn communication strategies by considering the joint utility of messages across all pairs of arms and using a Q-network architecture that decomposes the joint utility. Both theoretical and empirical evidence validate the effectiveness of our method in significantly improving RMAB performance across diverse problems.

AAMAS Conference 2025 Conference Paper

Towards Foundation-model-based Multiagent System to Accelerate AI for Social Impact

  • Yunfan Zhao
  • Niclas Boehmer
  • Aparna Taneja
  • Milind Tambe

AI for social impact (AI4SI) offers significant potential for addressing complex societal challenges in areas such as public health, agriculture, education, conservation, and public safety. However, existing AI4SI research is often labor-intensive and resource-demanding, limiting its accessibility and scalability; the standard approach is to design a (base-level) system tailored to a specific AI4SI problem. We propose the development of a novel meta-level multi-agent system designed to accelerate the development of such base-level systems, thereby reducing the computational cost and the burden on social impact domain experts and AI researchers. Leveraging advancements in foundation models and large language models, our proposed approach focuses on resource allocation problems providing help across the full AI4SI pipeline from problem formulation over solution design to impact evaluation. We highlight the ethical considerations and challenges inherent in deploying such systems and emphasize the importance of a human-in-the-loop approach to ensure the responsible and effective application of AI systems.

NeurIPS Conference 2024 Conference Paper

A Decision-Language Model (DLM) for Dynamic Restless Multi-Armed Bandit Tasks in Public Health

  • Nikhil Behari
  • Edwin Zhang
  • Yunfan Zhao
  • Aparna Taneja
  • Dheeraj Nagaraj
  • Milind Tambe

Restless multi-armed bandits (RMAB) have demonstrated success in optimizing resource allocation for large beneficiary populations in public health settings. Unfortunately, RMAB models lack flexibility to adapt to evolving public health policy priorities. Concurrently, Large Language Models (LLMs) have emerged as adept automated planners across domains of robotic control and navigation. In this paper, we propose a Decision Language Model (DLM) for RMABs, enabling dynamic fine-tuning of RMAB policies in public health settings using human-language commands. We propose using LLMs as automated planners to (1) interpret human policy preference prompts, (2) propose reward functions as code for a multi-agent RMAB environment, and (3) iterate on the generated reward functions using feedback from grounded RMAB simulations. We illustrate the application of DLM in collaboration with ARMMAN, an India-based non-profit promoting preventative care for pregnant mothers, that currently relies on RMAB policies to optimally allocate health worker calls to low-resource populations. We conduct a technology demonstration in simulation using the Gemini Pro model, showing DLM can dynamically shape policy outcomes using only human prompts as input.

AAMAS Conference 2024 Conference Paper

Efficient Public Health Intervention Planning Using Decomposition-Based Decision-focused Learning

  • Sanket Shah
  • Arun Suggala
  • Milind Tambe
  • Aparna Taneja

The declining participation of beneficiaries over time is a key concern in public health programs. A popular strategy for improving retention is to have health workers ‘intervene’ on beneficiaries at risk of dropping out. However, the availability and time of these health workers are limited resources. As a result, there has been a line of research on optimizing these limited intervention resources using Restless Multi-Armed Bandits (RMABs). The key technical barrier to using this framework in practice lies in the need to estimate the beneficiaries’ RMAB parameters from historical data. Recent research has shown that Decision-Focused Learning (DFL), which focuses on maximizing the beneficiaries’ adherence rather than predictive accuracy, improves the performance of intervention targeting using RMABs. Unfortunately, these gains come at a high computational cost because of the need to solve and evaluate the RMAB in each DFL training step. In this paper, we provide a principled way to exploit the structure of RMABs to speed up intervention planning by cleverly decoupling the planning for different beneficiaries. We use real-world data from an Indian NGO, ARMMAN, to show that our approach is up to two orders of magnitude faster than the state-of-the-art approach while also yielding superior model performance. This would enable the NGO to scale up deployments using DFL to potentially millions of mothers, ultimately advancing progress toward UNSDG 3. 1.

UAI Conference 2024 Conference Paper

Group Fairness in Predict-Then-Optimize Settings for Restless Bandits

  • Shresth Verma
  • Yunfan Zhao
  • Sanket Shah
  • Niclas Boehmer
  • Aparna Taneja
  • Milind Tambe

Restless multi-arm bandits (RMABs) are a model for sequentially allocating a limited number of resources to agents modeled as Markov Decision Processes. RMABs have applications in cellular networks, anti-poaching, and in particular, healthcare. For such high-stakes use cases, allocations are often required to treat different groups of agents (e. g. , defined by sensitive attributes) fairly. In addition to the fairness challenge, agents’ transition probabilities are often unknown and need to be learned in real-world problems. Thus, group fairness in RMABs requires us to simultaneously learn transition probabilities and how much budget we allocate to each group. Overcoming this key challenge ignored by previous work, we develop a decision-focused-learning pipeline to solve equitable RMABs, using a novel budget allocation algorithm to prevent disparity between groups. Our results on both synthetic and real-world large-scale datasets demonstrate that incorporating fair planning into the learning step greatly improves equity with little sacrifice in utility.

AAMAS Conference 2024 Conference Paper

Improving Mobile Maternal and Child Health Care Programs: Collaborative Bandits for Time Slot Selection

  • Soumyabrata Pal
  • Milind Tambe
  • Arun Suggala
  • Karthikeyan Shanmugam
  • Aparna Taneja

Maternal and child health is a global priority, reflected in the UN Sustainable Development Goal 3. 1. Mobile health (mHealth) programs, using automated voice messages, are a vital tool for NGOs to disseminate health information in underserved communities. However, these programs face challenges: limited beneficiary phone access and unknown time preferences hinder timely outreach, leading to poor engagement. We address this by formulating the time preference inference problem as a multi-agent multi-armed bandit optimization problem, where beneficiaries are modeled as agents, and time slots as arms. We introduce a novel online collaborative filtering framework that infers preferred time slots by collaborating across beneficiaries to quickly identify their preferred time slots. To highlight the scope and impact of this problem, we are working with Kilkari, the world’s largest maternal and child mHealth program serving millions in India every week. Kilkari faces substantial reattempt costs to improve call answer rates. Through extensive experiments on real-world data obtained from Kilkari, we demonstrate that our collaborative bandit framework significantly outperforms both existing policies used by the NGO, and popular non-collaborative bandit algorithms (e. g. , Upper Confidence Bound), both in terms of number of call retries, saving critical bandwidth that enables wider outreach, and by rapidly learning optimal time slots, improving beneficiary engagement and retention.

IJCAI Conference 2024 Conference Paper

Towards a Pretrained Model for Restless Bandits via Multi-arm Generalization

  • Yunfan Zhao
  • Nikhil Behari
  • Edward Hughes
  • Edwin Zhang
  • Dheeraj Nagaraj
  • Karl Tuyls
  • Aparna Taneja
  • Milind Tambe

Restless multi-arm bandits (RMABs) is a class of resource allocation problems with broad application in areas such as healthcare, online advertising, and anti-poaching. We explore several important question such as how to handle arms opting-in and opting-out over time without frequent retraining from scratch, how to deal with continuous state settings with nonlinear reward functions, which appear naturally in practical contexts. We address these questions by developing a pre-trained model (PreFeRMAB) based on a novel combination of three key ideas: (i) to enable fast generalization, we use train agents to learn from each other's experience; (ii) to accommodate streaming RMABs, we derive a new update rule for a crucial $\lambda$-network; (iii) to handle more complex continuous state settings, we design the algorithm to automatically define an abstract state based on raw observation and reward data. PreFeRMAB allows general zero-shot ability on previously unseen RMABs, and can be fine-tuned on specific instances in a more sample-efficient way than retraining from scratch. We theoretically prove the benefits of multi-arm generalization and empirically demonstrate the advantages of our approach on several challenging, real-world inspired problems.

AAMAS Conference 2024 Conference Paper

Towards Zero Shot Learning in Restless Multi-armed Bandits

  • Yunfan Zhao
  • Nikhil Behari
  • Edward Hughes
  • Edwin Zhang
  • Dheeraj Nagaraj
  • Karl Tuyls
  • Aparna Taneja
  • Milind Tambe

Restless multi-arm bandits (RMABs), a class of resource allocation problems with broad application in areas such as healthcare, online advertising, and anti-poaching, have recently been studied from a multi-agent reinforcement learning perspective. Prior RMAB research suffers from several limitations, e. g. , it fails to adequately address continuous states, and requires retraining from scratch when arms opt-in and opt-out over time, a common challenge in many real world applications. We propose a neural network-based pre-trained model that has general zero-shot ability on a wide range of previously unseen RMABs.

AAAI Conference 2023 Conference Paper

Flexible Budgets in Restless Bandits: A Primal-Dual Algorithm for Efficient Budget Allocation

  • Paula Rodriguez Diaz
  • Jackson A. Killian
  • Lily Xu
  • Arun Sai Suggala
  • Aparna Taneja
  • Milind Tambe

Restless multi-armed bandits (RMABs) are an important model to optimize allocation of limited resources in sequential decision-making settings. Typical RMABs assume the budget --- the number of arms pulled --- to be fixed for each step in the planning horizon. However, for realistic real-world planning, resources are not necessarily limited at each planning step; we may be able to distribute surplus resources in one round to an earlier or later round. In real-world planning settings, this flexibility in budget is often constrained to within a subset of consecutive planning steps, e.g., weekly planning of a monthly budget. In this paper we define a general class of RMABs with flexible budget, which we term F-RMABs, and provide an algorithm to optimally solve for them. We derive a min-max formulation to find optimal policies for F-RMABs and leverage gradient primal-dual algorithms to solve for reward-maximizing policies with flexible budgets. We introduce a scheme to sample expected gradients to apply primal-dual algorithms to the F-RMAB setting and make an otherwise computationally expensive approach tractable. Additionally, we provide heuristics that trade off solution quality for efficiency and present experimental comparisons of different F-RMAB solution approaches.

ICML Conference 2023 Conference Paper

Improved Policy Evaluation for Randomized Trials of Algorithmic Resource Allocation

  • Aditya Mate
  • Bryan Wilder
  • Aparna Taneja
  • Milind Tambe

We consider the task of evaluating policies of algorithmic resource allocation through randomized controlled trials (RCTs). Such policies are tasked with optimizing the utilization of limited intervention resources, with the goal of maximizing the benefits derived. Evaluation of such allocation policies through RCTs proves difficult, notwithstanding the scale of the trial, because the individuals’ outcomes are inextricably interlinked through resource constraints controlling the policy decisions. Our key contribution is to present a new estimator leveraging our proposed novel concept, that involves retrospective reshuffling of participants across experimental arms at the end of an RCT. We identify conditions under which such reassignments are permissible and can be leveraged to construct counterfactual trials, whose outcomes can be accurately ascertained, for free. We prove theoretically that such an estimator is more accurate than common estimators based on sample means – we show that it returns an unbiased estimate and simultaneously reduces variance. We demonstrate the value of our approach through empirical experiments on synthetic, semisynthetic as well as real case study data and show improved estimation accuracy across the board.

IJCAI Conference 2023 Conference Paper

Limited Resource Allocation in a Non-Markovian World: The Case of Maternal and Child Healthcare

  • Panayiotis Danassis
  • Shresth Verma
  • Jackson A. Killian
  • Aparna Taneja
  • Milind Tambe

The success of many healthcare programs depends on participants' adherence. We consider the problem of scheduling interventions in low resource settings (e. g. , placing timely support calls from health workers) to increase adherence and/or engagement. Past works have successfully developed several classes of Restless Multi-armed Bandit (RMAB) based solutions for this problem. Nevertheless, all past RMAB approaches assume that the participants' behaviour follows the Markov property. We demonstrate significant deviations from the Markov assumption on real-world data on a maternal health awareness program from our partner NGO, ARMMAN. Moreover, we extend RMABs to continuous state spaces, a previously understudied area. To tackle the generalised non-Markovian RMAB setting we (i) model each participant's trajectory as a time-series, (ii) leverage the power of time-series forecasting models to learn complex patterns and dynamics to predict future states, and (iii) propose the Time-series Arm Ranking Index (TARI) policy, a novel algorithm that selects the RMAB arms that will benefit the most from an intervention, given our future state predictions. We evaluate our approach on both synthetic data, and a secondary analysis on real data from ARMMAN, and demonstrate significant increase in engagement compared to the SOTA, deployed Whittle index solution. This translates to 16. 3 hours of additional content listened, 90. 8% more engagement drops prevented, and reaching more than twice as many high dropout-risk beneficiaries.

AAMAS Conference 2023 Conference Paper

Modeling Robustness in Decision-Focused Learning as a Stackelberg Game

  • Sonja Johnson-Yu
  • Kai Wang
  • Jessie Finocchiaro
  • Aparna Taneja
  • Milind Tambe

Predict-then-optimize is a common paradigm for optimization tasks situated in incomplete informational settings, in which an agent estimates missing parameters and then optimizes over these predicted parameters. One proposed improvement to this predict-thenoptimize framework is decision-focused learning, which establishes an end-to-end learning pipeline, allowing a predictive model to be tailored to the particular optimization task. The behavior of this predict-then-optimize framework in the presence of noise, however, is not well-understood. This is problematic because many data collection and annotation systems are inherently noisy, and the introduction of such noise could lead to poor downstream optimization. In this work, we aim to present results on robustness to label noise in decision-focused learning and traditional predictthen-optimize tasks using a Stackelberg game as the underlying framework of explanation. Our results suggest that playing the Stackelberg game in anticipation of label noise yields robustness in the predict-then-optimize framework at large, and that the optimal decision-focused learning Stackelberg solution continues to outperform the optimal traditional predict-then-optimize Stackelberg solution.

AAAI Conference 2023 Conference Paper

Optimistic Whittle Index Policy: Online Learning for Restless Bandits

  • Kai Wang
  • Lily Xu
  • Aparna Taneja
  • Milind Tambe

Restless multi-armed bandits (RMABs) extend multi-armed bandits to allow for stateful arms, where the state of each arm evolves restlessly with different transitions depending on whether that arm is pulled. Solving RMABs requires information on transition dynamics, which are often unknown upfront. To plan in RMAB settings with unknown transitions, we propose the first online learning algorithm based on the Whittle index policy, using an upper confidence bound (UCB) approach to learn transition dynamics. Specifically, we estimate confidence bounds of the transition probabilities and formulate a bilinear program to compute optimistic Whittle indices using these estimates. Our algorithm, UCWhittle, achieves sublinear O(H \sqrt{T log T}) frequentist regret to solve RMABs with unknown transitions in T episodes with a constant horizon H. Empirically, we demonstrate that UCWhittle leverages the structure of RMABs and the Whittle index policy solution to achieve better performance than existing online learning baselines across three domains, including one constructed from a real-world maternal and childcare dataset.

AAMAS Conference 2023 Conference Paper

Restless Multi-Armed Bandits for Maternal and Child Health: Results from Decision-Focused Learning

  • Shresth Verma
  • Aditya Mate
  • Kai Wang
  • Neha Madhiwalla
  • Aparna Hegde
  • Aparna Taneja
  • Milind Tambe

Mobile Health Awareness programs in underserved communities often suffer from diminishing engagement over time and health workers have to make live service calls to encourage beneficiaries’ participation. Owing to health workers’ limited availability, we consider the optimization problem of scheduling live service calls in a Maternal and Child Health Awareness Program and model it using Restless Multi-Armed Bandits (RMAB). Since the parameters of the RMAB formulation are unknown, a model is learnt to first predict the parameters of the RMAB problem, which is subsequently solved using the Whittle Index algorithm. However, this Predict-then-Optimize framework maximises for the predictive accuracy rather than the quality of the final solution. Decision Focused Learning (DFL) solves this mismatch by integrating the optimization problem in the learning pipeline. Previous works have only shown the applicability of DFL in simulation setting. In collaboration with an NGO, we conduct a large-scale field study consisting of 9000 beneficiaries for 6 weeks and track key engagement metrics in a mobile health awareness program. To the best of our knowledge this is the first real-world study involving Decision Focused Learning. We demonstrate that beneficiaries in the DFL group experience statistically significant reductions in cumulative engagement drop, while those in the Predict-then-Optimize group do not. This establishes the practicality of use of decision focused learning for real world problems. We also demonstrate that DFL learns a better decision boundary between the RMAB actions, and strategically predicts parameters for arms which contribute most to the final decision outcome.

AAAI Conference 2023 Conference Paper

Robust Planning over Restless Groups: Engagement Interventions for a Large-Scale Maternal Telehealth Program

  • Jackson A. Killian
  • Arpita Biswas
  • Lily Xu
  • Shresth Verma
  • Vineet Nair
  • Aparna Taneja
  • Aparna Hegde
  • Neha Madhiwalla

In 2020, maternal mortality in India was estimated to be as high as 130 deaths per 100K live births, nearly twice the UN's target. To improve health outcomes, the non-profit ARMMAN sends automated voice messages to expecting and new mothers across India. However, 38% of mothers stop listening to these calls, missing critical preventative care information. To improve engagement, ARMMAN employs health workers to intervene by making service calls, but workers can only call a fraction of the 100K enrolled mothers. Partnering with ARMMAN, we model the problem of allocating limited interventions across mothers as a restless multi-armed bandit (RMAB), where the realities of large scale and model uncertainty present key new technical challenges. We address these with GROUPS, a double oracle–based algorithm for robust planning in RMABs with scalable grouped arms. Robustness over grouped arms requires several methodological advances. First, to adversarially select stochastic group dynamics, we develop a new method to optimize Whittle indices over transition probability intervals. Second, to learn group-level RMAB policy best responses to these adversarial environments, we introduce a weighted index heuristic. Third, we prove a key theoretical result that planning over grouped arms achieves the same minimax regret--optimal strategy as planning over individual arms, under a technical condition. Finally, using real-world data from ARMMAN, we show that GROUPS produces robust policies that reduce minimax regret by up to 50%, halving the number of preventable missed voice messages to connect more mothers with life-saving maternal health information.

AAAI Conference 2023 Conference Paper

Scalable Decision-Focused Learning in Restless Multi-Armed Bandits with Application to Maternal and Child Health

  • Kai Wang
  • Shresth Verma
  • Aditya Mate
  • Sanket Shah
  • Aparna Taneja
  • Neha Madhiwalla
  • Aparna Hegde
  • Milind Tambe

This paper studies restless multi-armed bandit (RMAB) problems with unknown arm transition dynamics but with known correlated arm features. The goal is to learn a model to predict transition dynamics given features, where the Whittle index policy solves the RMAB problems using predicted transitions. However, prior works often learn the model by maximizing the predictive accuracy instead of final RMAB solution quality, causing a mismatch between training and evaluation objectives. To address this shortcoming, we propose a novel approach for decision-focused learning in RMAB that directly trains the predictive model to maximize the Whittle index solution quality. We present three key contributions: (i) we establish differentiability of the Whittle index policy to support decision-focused learning; (ii) we significantly improve the scalability of decision-focused learning approaches in sequential problems, specifically RMAB problems; (iii) we apply our algorithm to a previously collected dataset of maternal and child health to demonstrate its performance. Indeed, our algorithm is the first for decision-focused learning in RMAB that scales to real-world problem sizes.

IJCAI Conference 2022 Conference Paper

ADVISER: AI-Driven Vaccination Intervention Optimiser for Increasing Vaccine Uptake in Nigeria

  • Vineet Nair
  • Kritika Prakash
  • Michael Wilbur
  • Aparna Taneja
  • Corrine Namblard
  • Oyindamola Adeyemo
  • Abhishek Dubey
  • Abiodun Adereni

More than 5 million children under five years die from largely preventable or treatable medical conditions every year, with an overwhelmingly large proportion of deaths occurring in under-developed countries with low vaccination uptake. One of the United Nations' sustainable development goals (SDG 3) aims to end preventable deaths of newborns and children under five years of age. We focus on Nigeria, where the rate of infant mortality is appalling. We collaborate with HelpMum, a large non-profit organization in Nigeria, to design and optimize the allocation of heterogeneous health interventions under uncertainty to increase vaccination uptake, the first such collaboration in Nigeria. Our framework, ADVISER: AI-Driven Vaccination Intervention Optimiser, is based on an integer linear program that seeks to maximize the cumulative probability of successful vaccination. Our optimization formulation is intractable in practice. We present a heuristic approach that enables us to solve the problem for real-world use-cases. We also present theoretical bounds for the heuristic method. Finally, we show that the proposed approach outperforms baseline methods in terms of vaccination uptake through experimental evaluation. HelpMum is currently planning a pilot program based on our approach to be deployed in the largest city of Nigeria, which would be the first deployment of an AI-driven vaccination uptake program in the country and hopefully, pave the way for other data-driven programs to improve health outcomes in Nigeria.

AAAI Conference 2022 Conference Paper

Field Study in Deploying Restless Multi-Armed Bandits: Assisting Non-profits in Improving Maternal and Child Health

  • Aditya Mate
  • Lovish Madaan
  • Aparna Taneja
  • Neha Madhiwalla
  • Shresth Verma
  • Gargi Singh
  • Aparna Hegde
  • Pradeep Varakantham

The widespread availability of cell phones has enabled nonprofits to deliver critical health information to their beneficiaries in a timely manner. This paper describes our work to assist non-profits that employ automated messaging programs to deliver timely preventive care information to beneficiaries (new and expecting mothers) during pregnancy and after delivery. Unfortunately, a key challenge in such information delivery programs is that a significant fraction of beneficiaries drop out of the program. Yet, non-profits often have limited health-worker resources (time) to place crucial service calls for live interaction with beneficiaries to prevent such engagement drops. To assist non-profits in optimizing this limited resource, we developed a Restless Multi-Armed Bandits (RMABs) system. One key technical contribution in this system is a novel clustering method of offline historical data to infer unknown RMAB parameters. Our second major contribution is evaluation of our RMAB system in collaboration with an NGO, via a real-world service quality improvement study. The study compared strategies for optimizing service calls to 23003 participants over a period of 7 weeks to reduce engagement drops. We show that the RMAB group provides statistically significant improvement over other comparison groups, reducing ∼ 30% engagement drops. To the best of our knowledge, this is the first study demonstrating the utility of RMABs in real world public health settings. We are transitioning our RMAB system to the NGO for real-world use.

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