Munindar P. Singh

AAMAS Conference 2026 Conference Paper

Guiding Sociotechnical Systems toward Value-Norm Equilibrium

• Nirav Ajmeri
• Marina De Vos
• Davide Dell'Anna
• Pradeep K. Murukannaiah
• Vivek Nallur
• Luis G. Nardin
• Munindar P. Singh

Values and norms are complementary constructs that undergird prosocialbehaviorinsociotechnicalsystems(STSs). Whereasvalues are intrinsic motivators for prosocial behavior, norms are extrinsic motivators for meeting mutual expectations. An STS is in equilibrium when the values of its member actors and the norms that govern it align with each other. Such an equilibrium is not permanent as actors join or leave the STS, and their values and norms evolve. In general, an STS must be guided toward equilibrium by systematically refining the norm specifications and influencing the values of its member actors. We formulate the challenges involved in building systematic methods to detect misalignment and guide the STS toward, and maintain, value-norm equilibrium.

AAMAS Conference 2026 Conference Paper

Peach: Program Each Agent and Communicate Howsoever

• Amit K. Chopra
• Samuel H. Christie V
• Munindar P. Singh

We contribute Peach, an approach to program an agent that decouples reasoning about the meanings of communications from the underlying communication infrastructure. Peach’s conceptual component is a programming model based on Langshaw, a protocol language based on communicative actions, whose abstractions promotemeaningandhidecoordinationdetails. Peach’scomputational component is an adapter that can be configured for different infrastructures. We provide an operational semantics for this adapter that maps our programming model to two main kinds of infrastructure: decentralized (via messages) or shared-memory.

JAAMAS Journal 2026 Journal Article

Synthesizing Coordination Requirements for Heterogeneous Autonomous Agents

• Munindar P. Singh

Abstract As agents move into ever more important applications, there is a natural growth in interest in techniques for synthesizing multiagent systems. We describe an approach for engineering the coordination requirements of a multiagent system based on an analysis of conversation instances extracted from usage scenarios. This approach exploits the notion of Dooley graphs that were recently introduced to the multiagent systems community from the linguistics and discourse analysis literature. We show how, with a few key modifications, Dooley graphs can be used to generate coordination requirements and constraints on the behavior models of the agents participating in a multiagent system. Our present approach is embodied in the context of our recent work on a distributed coordination service for heterogeneous, autonomous agents. This approach takes as input (a) agent skeletons, giving compact descriptions of the given agents in terms of their events that are significant for coordination, as well as (b) relationships among the events occurring in these skeletons. A natural question is how may the skeletons and relationships be produced in the first place. It turns out that a methodology that begins with Dooley graphs can readily yield the skeletons and relationships needed to achieve the desired coordination. Consequently, our approach combines the benefits of an intuitive methodology with a formal and distributed framework for developing multiagent systems from autonomous agents.

JAAMAS Journal 2026 Journal Article

Verifying Compliance with Commitment Protocols

• Mahadevan Venkatraman
• Munindar P. Singh

Abstract Interaction protocols are specific, often standard, constraints on the behaviors of autonomous agents in a multiagent system. Protocols are essential to the functioning of open systems, such as those that arise in most interesting web applications. A variety of common protocols in negotiation and electronic commerce are best treated as commitment protocols, which are defined, or at least analyzed, in terms of the creation, satisfaction, or manipulation of the commitments among the participating agents. When protocols are employed in open environments, such as the Internet, they must be executed by agents that behave more or less autonomously and whose internal designs are not known. In such settings, therefore, there is a risk that the participating agents may fail to comply with the given protocol. Without a rigorous means to verify compliance, the very idea of protocols for interoperation is subverted. We develop an approach for testing whether the behavior of an agent complies with a commitment protocol. Our approach requires the specification of commitment protocols in temporal logic, and involves a novel way of synthesizing and applying ideas from distributed computing and logics of program.

AIJ Journal 2025 Journal Article

Argus: Programming with communication protocols in a belief-desire-intention architecture

• Samuel H. Christie
• Munindar P. Singh
• Amit K. Chopra

Protocols model multiagent systems (MAS) by capturing the communications between its agents. Belief-Desire-Intention (BDI) architectures provide an attractive way for organizing an agent in terms of cognitive concepts. Current BDI approaches, however, lack adequate support for engineering protocol-based agents. We describe Argus, an approach that melds recent advances in flexible, declarative communication protocols with BDI architectures. For concreteness, we adopt Jason as an exemplar of the BDI paradigm and show how to support protocol-based reasoning in it. Specifically, Argus contributes (1) a novel architecture and formal operational semantics combining protocols and BDI; (2) a code generation-based programming model that guides the implementation of agents; and (3) integrity checking for incoming and outgoing messages that help ensure that the agents are well-behaved. The Argus conceptual architecture builds quite naturally on top of Jason. Thus, Argus enables building more flexible multiagent systems while using a BDI architecture than is currently possible.

AAMAS Conference 2025 Conference Paper

Azorus: Commitments over Protocols for BDI Agents

• Amit K. Chopra
• Matteo Baldoni
• Samuel H. Christie
• Munindar P. Singh

Commitments support flexible interactions between agents by capturing the meaning of their interactions. However, commitmentbased reasoning is not adequately supported in agent programming models. We contribute Azorus, a programming model based on declarative specifications centered on commitments and aligned with information protocols. Azorus supports reasoning about goals and commitments and combines modeling of commitments and protocols, thereby uniting three leading declarative approaches to engineering decentralized multiagent systems. Specifically, we realize Azorus over three existing technology suites: (1) Jason, a popular BDI-based programming model; (2) Cupid, a formal language and query-based model for commitments; and (3) BSPL, a language and its associated tools for information protocols, including Jason programming. We implement Azorus and demonstrate how it enables capturing interesting patterns of business logic.

AAMAS Conference 2025 Conference Paper

Gricean Norms as a Basis for Effective Collaboration

• Fardin Saad
• Pradeep K. Murukannaiah
• Munindar P. Singh

Effective human-AI collaboration hinges not only on the AI agent’s ability to follow explicit instructions but also on its capacity to navigate ambiguity, incompleteness, invalidity, and irrelevance in communication. Gricean conversational and inference norms facilitate collaboration by aligning unclear instructions with cooperative principles. We propose a normative framework that integrates Gricean norms and cognitive frameworks—common ground, relevance theory, and theory of mind—into large language model (LLM) based agents. The normative framework adopts the Gricean maxims of quantity, quality, relation, and manner, along with inference, as Gricean norms to interpret unclear instructions, which are: ambiguous, incomplete, invalid, or irrelevant. Within this framework, we introduce Lamoids, GPT-4 powered agents designed to collaborate with humans. To assess the influence of Gricean norms in human- AI collaboration, we evaluate two versions of a Lamoid: one with norms and one without. In our experiments, a Lamoid collaborates with a human to achieve shared goals in a grid world (Doors, Keys, and Gems) by interpreting both clear and unclear natural language instructions. Our results reveal that the Lamoid with Gricean norms achieves higher task accuracy and generates clearer, more accurate, and contextually relevant responses than the Lamoid without norms. This improvement stems from the normative framework, which enhances the agent’s pragmatic reasoning, fostering effective human-AI collaboration and enabling context-aware communication in LLM-based agents.

AAAI Conference 2025 Conference Paper

Orpheus: Engineering Multiagent Systems via Communicating Agents

• Matteo Baldoni
• Samuel H. Christie V
• Munindar P. Singh
• Amit K. Chopra

We propose Orpheus, a novel programming model for communicating agents based on information protocols and realized using cognitive programming. Whereas traditional models are focused on reactions to handle incoming messages, Orpheus supports organizing the internal logic of an agent based on its goals. We give an operational semantics for Orpheus and implement this semantics in an adapter to help build agents. We use the adapter to demonstrate how Orpheus simplifies the programming of decentralized multiagent systems compared to the reactive programming model.

AAMAS Conference 2025 Conference Paper

Orpheus: Programming Protocol-Based BDI Agents

• Matteo Baldoni
• Samuel H. Christie
• Munindar P. Singh
• Amit K. Chopra

We demonstrate Orpheus, a novel programming model for engineering BDI agents that communicate on the basis of protocols. In Orpheus, protocols are specified in BSPL and agents are implemented in Jason. Given a protocol, Orpheus tooling generates a Jason adapter that exposes a simple interface for sending messages based on protocol state. Orpheus shines in the implementation of flexible, loosely-coupled agents, long a challenge for BDI-based agent programming approaches. Demonstration video: https: //di. unito. it/orpheusvid

JAIR Journal 2025 Journal Article

Prosociality in Microtransit

• Divya Sundaresan
• Akhira Watson
• Eleni Bardaka
• Crystal Chen Lee
• Christopher B. Mayhorn
• Munindar P. Singh

We study (public) microtransit, a type of transportation service wherein a municipality offers point-to-point rides to residents, for a fixed, nominal fare. Microtransit exemplifies practical resource allocation problems that are often over-constrained in that not all ride requests (pickup and dropoff locations at specified times) can be satisfied or satisfied only by violating soft goals such as sustainability, and where economic signals (e.g., surge pricing) are not applicable—they would lead to unethical outcomes by effectively coercing poor people. We posit that instead of taking rider preferences as fixed, shaping them prosocially will lead to improved societal outcomes. Prosociality refers to an attitude or behavior that is intended to benefit others. This paper demonstrates a computational approach to prosociality in the context of a (public) microtransit service for disadvantaged riders. Prosociality appears as a willingness to adjust one’s pickup and dropoff times and locations to accommodate the schedules of others and to enable sharing rides (which increases the number of riders served with the same resources). This paper describes an interdisciplinary study of prosociality in microtransit between a transportation researcher, psychologists, a social scientist, and AI researchers. Our contributions are these: (1) empirical support for the viability of prosociality in microtransit (and constraints on it) through interviews with drivers and focus groups of riders; (2) a prototype mobile app demonstrating how our prosocial intervention can be combined with the transportation backend; (3) a reinforcement learning approach to model a rider and determine the best interventions to persuade that rider toward prosociality; and (4) a cognitive model of rider personas to enable evaluation of alternative interventions.

IJCAI Conference 2025 Conference Paper

Requirement Patterns for Engineering Multiagent Interaction Protocols

• Amit K. Chopra
• Samuel H. Christie V.
• Munindar P. Singh

An interaction protocol specifies how the member agents of a decentralized multiagent system may communicate to satisfy their respective stakeholders' requirements. We focus on information protocols, which are fully declarative specifications of interaction and support asynchronous communication. We offer Mambo, an approach for protocol design. Mambo identifies common patterns of requirements, provides a notation to express them, and a verification procedure. Mambo incorporates heuristics to generate small internal representations for efficiency. Experimental results demonstrate Mambo's effectiveness on practical protocols.

IJCAI Conference 2024 Conference Paper

Empathy and AI: Achieving Equitable Microtransit for Underserved Communities

• Eleni Bardaka
• Pascal Van Hentenryck
• Crystal Chen Lee
• Christopher B. Mayhorn
• Kai Monast
• Samitha Samaranayake
• Munindar P. Singh

This paper describes a newly launched project that will produce a new approach to public microtransit for underserved communities. Public microtransit cannot rely on pricing signals to manage demand, and current approaches face the challenges of simultaneously being underutilized and overextended. This project conceives of the setting as a sociotechnical system. Its main idea is to engage users through AI agents in conjunction with platform constraints to find solutions that purely technical conceptions cannot find. The project was specified over an intense series of discussions with key stakeholders (riders, city government, and nongovernmental agencies) and brings together expertise in the disciplines of AI, Operations Research, Urban Planning, Psychology, and Community Development. The project will culminate in a pilot study, results from which will facilitate the transfer of its technology to additional communities.

IJCAI Conference 2024 Conference Paper

Langshaw: Declarative Interaction Protocols Based on Sayso and Conflict

• Munindar P. Singh
• Samuel H. Christie V.
• Amit K. Chopra

Current languages for specifying multiagent protocols either over-constrain protocol enactments or complicate capturing their meanings. We propose Langshaw, a declarative protocol language based on (1) sayso, a new construct that captures who has priority over setting each attribute, and (2) nono and nogo, two constructs to capture conflicts between actions. Langshaw combines flexibility with an information model to express meaning. We give a formal semantics for Langshaw, procedures for determining the safety and liveness of a protocol, and a method to generate a message-oriented protocol (embedding needed coordination) suitable for flexible asynchronous enactment.

AAMAS Conference 2024 Conference Paper

Norm Enforcement with a Soft Touch: Faster Emergence, Happier Agents

• Sz-Ting Tzeng
• Nirav Ajmeri
• Munindar P. Singh

A multiagent system is a society of autonomous agents whose interactions can be regulated via social norms. In general, the norms of a society are not hardcoded but emerge from the agents’ interactions. Specifically, how the agents in a society react to each other’s behavior and respond to the reactions of others determines which norms emerge in the society. We think of these reactions by an agent to the satisfactory or unsatisfactory behaviors of another agent as communications from the first agent to the second agent. Understanding these communications is a kind of social intelligence: these communications provide natural drivers for norm emergence by pushing agents toward certain behaviors, which can become established as norms. Whereas it is well-known that sanctioning can lead to the emergence of norms, we posit that a broader kind of social intelligence can prove more effective in promoting cooperation in a multiagent system. Accordingly, we develop Nest, a framework that models social intelligence via a wider variety of communications and understanding of them than in previous work. To evaluate Nest, we develop a simulated pandemic environment and conduct simulation experiments to compare Nest with baselines considering a combination of three kinds of social communication: sanction, tell, and hint. We find that societies formed of Nest agents achieve norms faster. Moreover, Nest agents effectively avoid undesirable consequences, which are negative sanctions and deviation from goals, and yield higher satisfaction for themselves than baseline agents despite requiring only an equivalent amount of information.

AAMAS Conference 2024 Conference Paper

Toward a Normative Approach for Resilient Multiagent Systems: A Summary

• Geeta Mahala
• Ozgur Kafali
• Hoa Khanh Dam
• Aditya Ghose
• Munindar P. Singh

We model a multiagent system (MAS) in socio-technical terms, combining a social layer consisting of norms with a technical layer consisting of actions that the agents execute. We express stakeholder needs to ensure that a MAS demonstrates resilience, allowing it to recover effectively from failures within a brief timeframe. This extended abstract presents a framework that computes probabilistic and temporal guarantees on whether the underlying requirements are met or, if failed, recovered. An important contribution of the framework is that it shows how the social and technical layers can be modeled jointly to enable the construction of resilient systems of autonomous agents. This paper facilitates specification refinement through methodological guidelines, emphasizing joint modeling of social and technical layers. We demonstrate our framework using a manufacturing scenario with competing public, industrial, and environmental requirements. This is an extended abstract of our JAAMAS paper available online [11].

ECAI Conference 2024 Conference Paper

Value-Based Rationales Improve Social Experience: A Multiagent Simulation Study

• Sz-Ting Tzeng
• Nirav Ajmeri
• Munindar P. Singh

We propose Exanna, a framework to realize agents that incorporate values in decision making. An Exanna agent considers the values of itself and others when providing rationales for its actions and evaluating the rationales provided by others. Via multiagent simulation, we demonstrate that considering values in decision making and producing rationales, especially for norm-deviating actions, leads to (1) higher conflict resolution, (2) better social experience, (3) higher privacy, and (4) higher flexibility.

JAAMAS Journal 2023 Journal Article

A normative approach for resilient multiagent systems

• Geeta Mahala
• Özgür Kafalı
• Munindar P. Singh

Abstract We model a multiagent system (MAS) in socio-technical terms, combining a social layer consisting of norms with a technical layer consisting of actions that the agents execute. This approach emphasizes autonomy, and makes assumptions about both the social and technical layers explicit. Autonomy means that agents may violate norms. In our approach, agents are computational entities, with each representing a different stakeholder. We express stakeholder requirements of the form that a MAS is resilient in that it can recover (sufficiently) from a failure within a (sufficiently short) duration. We present ReNo, a framework that computes probabilistic and temporal guarantees on whether the underlying requirements are met or, if failed, recovered. ReNo supports the refinement of the specification of a socio-technical system through methodological guidelines to meet the stated requirements. An important contribution of ReNo is that it shows how the social and technical layers can be modeled jointly to enable the construction of resilient systems of autonomous agents. We demonstrate ReNo using a manufacturing scenario with competing public, industrial, and environmental requirements.

AAMAS Conference 2023 Conference Paper

Interaction-Oriented Programming: Intelligent, Meaning-Based Multiagent Systems

• Amit K. Chopra
• Samuel H. Christie, V
• Munindar P. Singh

Interaction-Oriented Programming (IOP) is an approach for engineering decentralized multiagent systems based in the idea of modeling interaction meaning. Modeling meaning enables agents to make flexible decentralized decisions. IOP addresses the key architectural elements of multiagent systems, from communication services for messaging to protocols and norms. In this demo, we showcase the tools developed over the last decade that enable specifying, verifying, and implementing meaning-based, decentralized multiagent systems.

AAMAS Conference 2023 Conference Paper

Kiko: Programming Agents to Enact Interaction Models

• Samuel H. Christie, V
• Munindar P. Singh
• Amit K. Chopra

Realizing a multiagent system involves implementing member agents who interact based on a protocol while making decisions in a decentralized manner. Current programming models for agents offer poor abstractions for decision making and fail to adequately bridge an agent’s internal decision logic with its public decisions. We present Kiko, a protocol-based programming model for agents. To implement an agent, a programmer writes one or more decision makers, each of which chooses from among a set of valid decisions and makes mutually compatible decisions on what messages to send. By completely abstracting away the underlying communication service and by supporting practical decision-making patterns, Kiko enables agent developers to focus on business logic. We provide an operational semantics for Kiko and establish that Kiko agents are protocol compliant and able to realize any protocol enactment.

AIJ Journal 2023 Journal Article

Maintenance commitments: Conception, semantics, and coherence

• Pankaj Telang
• Munindar P. Singh
• Neil Yorke-Smith

Social commitments are recognized as an abstraction that enables flexible coordination between autonomous agents. We make these contributions. First, we introduce and formalize a concept of a maintenance commitment, a kind of social commitment characterized by a maintenance condition whose truthhood an agent commits to maintain. This concept of maintenance commitments enables us to capture a richer variety of real-world scenarios than possible using achievement commitments with a temporal condition. Second, we develop a rule-based operational semantics, by which we study the relationship between agents' achievement and maintenance goals, achievement commitments, and maintenance commitments. Third, we motivate a notion of coherence between an agents' achievement and maintenance cognitive and social constructs, and prove that, under specified conditions, the goals and commitments of both rational agents individually and of a multiagent system altogether are coherent. Fourth, we illustrate our approach with a detailed real-world scenario from an aerospace aftermarket domain.

AAMAS Conference 2023 Conference Paper

Mandrake: Multiagent Systems as a Basis for Programming Fault-Tolerant Decentralized Applications

• Samuel H. Christie, V
• Munindar P. Singh
• Amit K. Chopra

We define a decentralized software application as one that consists of autonomous agents that communicate through asynchronous messaging. Constructing a decentralized application involves designing agents as independent local computations that coordinate to realize the application’s requirements. Moreover, a decentralized application is susceptible to faults manifested as message loss, delay, and reordering. We contribute Mandrake, a programming model for decentralized applications that addresses these challenges. Specifically, we adopt the construct of an information protocol that specifies messaging between agents purely in causal terms and can be correctly enacted by agents in a shared-nothing environment over nothing more than unreliable, unordered transport. Mandrake facilitates (1) implementing protocol-compliant agents by introducing a programming model; (2) transforming fragile protocols into fault-tolerant ones with simple annotations; and (3) a declarative policy language that makes it easy to implement fault-tolerance in agents based on the capabilities in protocols. In obviating the reliance on reliability and ordering guarantees in the communication infrastructure, Mandrake achieves some of the goals of the founders of networked computing from the 1970s.

IJCAI Conference 2023 Conference Paper

Norm Deviation in Multiagent Systems: A Foundation for Responsible Autonomy

• Amika M. Singh
• Munindar P. Singh

The power of norms in both human societies and sociotechnical systems arises from the facts that (1) societal norms, including laws and policies, characterize acceptable behavior in high-level terms and (2) they are not hard controls and can be deviated from. Thus, the design of responsibly autonomous agents faces an essential tension: these agents must both (1) respect applicable norms and (2) deviate from those norms when blindly following them may lead to diminished outcomes. We propose a conceptual foundation for norm deviation. As a guiding framework, we adopt Habermas's theory of communicative action comprising objective, subjective, and practical validity claims regarding the suitability of deviation. Our analysis thus goes beyond previous studies of norm deviation and yields reasoning guidelines uniting norms and values by which to develop responsible agents.

AAAI Conference 2022 Conference Paper

Consent as a Foundation for Responsible Autonomy

• Munindar P. Singh

This paper focuses on a dynamic aspect of responsible autonomy, namely, to make intelligent agents be responsible at run time. That is, it considers settings where decision making by agents impinges upon the outcomes perceived by other agents. For an agent to act responsibly, it must accommodate the desires and other attitudes of its users and, through other agents, of their users. The contribution of this paper is twofold. First, it provides a conceptual analysis of consent, its benefits and misuses, and how understanding consent can help achieve responsible autonomy. Second, it outlines challenges for AI (in particular, for agents and multiagent systems) that merit investigation to form as a basis for modeling consent in multiagent systems and applying consent to achieve responsible autonomy.

JAAMAS Journal 2022 Journal Article

Mandrake: multiagent systems as a basis for programming fault-tolerant decentralized applications

• Samuel H. Christie V
• Amit K. Chopra
• Munindar P. Singh

Abstract We conceptualize a decentralized software application as one constituted from autonomous agents that communicate via asynchronous messaging. Modern software paradigms such as microservices and settings such as the Internet of Things evidence a growing interest in decentralized applications. Constructing a decentralized application involves designing agents as independent local computations that coordinate successfully to realize the application’s requirements. Moreover, a decentralized application is susceptible to faults manifested as message loss, delay, and reordering. We contribute Mandrake, a programming model for decentralized applications that tackles these challenges without relying on infrastructure guarantees. Specifically, we adopt the construct of an information protocol that specifies messaging between agents purely in causal terms and can be correctly enacted by agents in a shared-nothing environment over nothing more than unreliable, unordered transport. Mandrake facilitates (1) implementing protocol-compliant agents by introducing a programming model; (2) transforming protocols into fault-tolerant ones with simple annotations; and (3) a declarative policy language that makes it easy to implement fault-tolerance in agents based on the capabilities in protocols. Mandrake’s significance lies in demonstrating a straightforward approach for constructing decentralized applications without relying on coordination mechanisms in the infrastructure, thus achieving some of the goals of the founders of networked computing from the 1970s.

AAMAS Conference 2022 Conference Paper

Pippi: Practical Protocol Instantiation

• Samuel H. Christie
• Amit K. Chopra
• Munindar P. Singh

A protocol specifies interactions between roles, which together constitute a multiagent system (MAS). Enacting a protocol presupposes that agents are bound to the its roles. Existing protocol-based approaches, however, do not adequately treat the practical aspects of how roles bindings come about. Pippi addresses this problem of MAS instantiation. It proposes the notion of a metaprotocol, enacting which instantiates a MAS suitable for enacting a given protocol. Pippi demonstrates the subtleties involved in instantiating MAS arising from protocol composition, correlation, and decentralization. To address these subtleties and further support practical application patterns, we introduce an enhanced protocol language, with support for parameter types (including role and protocol typed parameters, for metaprotocols), interface flexibility, and binding constraints. We discuss the realization of our approach through an extended agent architecture, including the novel concept of a MAS adapter for contact management. We evaluate Pippi’s expressiveness by demonstrating common patterns for agent discovery.

TAAS Journal 2022 Journal Article

Prosocial Norm Emergence in Multi-agent Systems

• Mehdi Mashayekhi
• Nirav Ajmeri
• George F. List
• Munindar P. Singh

Multi-agent systems provide a basis for developing systems of autonomous entities and thus find application in a variety of domains. We consider a setting where not only the member agents are adaptive but also the multi-agent system viewed as an entity in its own right is adaptive. Specifically, the social structure of a multi-agent system can be reflected in the social norms among its members. It is well recognized that the norms that arise in society are not always beneficial to its members. We focus on prosocial norms, which help achieve positive outcomes for society and often provide guidance to agents to act in a manner that takes into account the welfare of others. Specifically, we propose Cha, a framework for the emergence of prosocial norms. Unlike previous norm emergence approaches, Cha supports continual change to a system (agents may enter and leave) and dynamism (norms may change when the environment changes). Importantly, Cha agents incorporate prosocial decision-making based on inequity aversion theory, reflecting an intuition of guilt arising from being antisocial. In this manner, Cha brings together two important themes in prosociality: decision-making by individuals and fairness of system-level outcomes. We demonstrate via simulation that Cha can improve aggregate societal gains and fairness of outcomes.

AAAI Conference 2021 Conference Paper

Maintenance of Social Commitments in Multiagent Systems

• Pankaj Telang
• Munindar P. Singh
• Neil Yorke-Smith

We introduce and formalize a concept of a maintenance commitment, a kind of social commitment characterized by states whose truthhood an agent commits to maintain. This concept of maintenance commitments enables us to capture a richer variety of real-world scenarios than possible using achievement commitments with a temporal condition. By developing a rule-based operational semantics, we study the relationship between agents’ achievement and maintenance goals, achievement commitments, and maintenance commitments. We motivate a notion of coherence which captures alignment between an agents’ achievement and maintenance cognitive and social constructs, and prove that, under specified conditions, the goals and commitments of both rational agents individually and of a multiagent system are coherent.

TIST Journal 2021 Journal Article

Nova: Value-based Negotiation of Norms

• Reyhan Aydoğan
• Özgür Kafali
• Furkan Arslan
• Catholijn M. Jonker
• Munindar P. Singh

Specifying a normative multiagent system (nMAS) is challenging, because different agents often have conflicting requirements. Whereas existing approaches can resolve clear-cut conflicts, tradeoffs might occur in practice among alternative nMAS specifications with no apparent resolution. To produce an nMAS specification that is acceptable to each agent, we model the specification process as a negotiation over a set of norms. We propose an agent-based negotiation framework, where agents’ requirements are represented as values (e.g., patient safety, privacy, and national security), and an agent revises the nMAS specification to promote its values by executing a set of norm revision rules that incorporate ontology-based reasoning. To demonstrate that our framework supports creating a transparent and accountable nMAS specification, we conduct an experiment with human participants who negotiate against our agent. Our findings show that our negotiation agent reaches better agreements (with small p -value and large effect size) faster than a baseline strategy. Moreover, participants perceive that our agent enables more collaborative and transparent negotiations than the baseline (with small p -value and large effect size in particular settings) toward reaching an agreement.

IJCAI Conference 2021 Conference Paper

Tango: Declarative Semantics for Multiagent Communication Protocols

• Munindar P. Singh
• Samuel H. Christie V.

A flexible communication protocol is necessary to build a decentralized multiagent system whose member agents are not coupled to each other's decision making. Information-based protocol languages capture a protocol in terms of causality and integrity constraints based on the information exchanged by the agents. Thus, they enable highly flexible enactments in which the agents proceed asynchronously and messages may be arbitrarily reordered. However, the existing semantics for such languages can produce a large number of protocol enactments, which makes verification of a protocol property intractable. This paper formulates a protocol semantics declaratively via inference rules that determine when a message emission or reception becomes enabled during an enactment, and its effect on the local state of an agent. The semantics enables heuristics for determining when alternative extensions of a current enactment would be equivalent, thereby helping produce parsimonious models and yielding improved protocol verification methods.

JAIR Journal 2020 Journal Article

An Evaluation of Communication Protocol Languages for Engineering Multiagent Systems

• Amit K Chopra
• Samuel H Christie V
• Munindar P. Singh

Communication protocols are central to engineering decentralized multiagent systems. Modern protocol languages are typically formal and address aspects of decentralization, such as asynchrony. However, modern languages differ in important ways in their basic abstractions and operational assumptions. This diversity makes a comparative evaluation of protocol languages a challenging task. We contribute a rich evaluation of diverse and modern protocol languages. Among the selected languages, Scribble is based on session types; Trace-C and Trace-F on trace expressions; HAPN on hierarchical state machines, and BSPL on information causality. Our contribution is four-fold. One, we contribute important criteria for evaluating protocol languages. Two, for each criterion, we compare the languages on the basis of whether they are able to specify elementary protocols that go to the heart of the criterion. Three, for each language, we map our findings to a canonical architecture style for multiagent systems, highlighting where the languages depart from the architecture. Four, we identify design principles for protocol languages as guidance for future research.

JAIR Journal 2019 Journal Article

A Coupled Operational Semantics for Goals and Commitments

• Pankaj R. Telang
• Munindar P. Singh
• Neil Yorke-Smith

Commitments capture how an agent relates to another agent, whereas goals describe states of the world that an agent is motivated to bring about. Commitments are elements of the social state of a set of agents whereas goals are elements of the private states of individual agents. It makes intuitive sense that goals and commitments are understood as being complementary to each other. More importantly, an agent's goals and commitments ought to be coherent, in the sense that an agent's goals would lead it to adopt or modify relevant commitments and an agent's commitments would lead it to adopt or modify relevant goals. However, despite the intuitive naturalness of the above connections, they have not been adequately studied in a formal framework. This article provides a combined operational semantics for goals and commitments by relating their respective life cycles as a basis for how these concepts (1) cohere for an individual agent and (2) engender cooperation among agents. Our semantics yields important desirable properties of convergence of the configurations of cooperating agents, thereby delineating some theoretically well-founded yet practical modes of cooperation in a multiagent system.

AAMAS Conference 2019 Conference Paper

Applying Norms and Sanctions to Promote Cybersecurity Hygiene

• Shubham Goyal
• Nirav Ajmeri
• Munindar P. Singh

Cybersecurity breaches cause enormous harm to the safety, privacy, and prosperity of individuals and organizations. Many security breaches occur due to people not following security regulations such as applying software patches, updating software applications, and so on. We term these regulations as cybersecurity hygiene. This paper investigates different sanctioning mechanisms with respect to the success in establishing these regulations for cybersecurity hygiene. Our findings have implications for workforce training to promote cybersecurity.

AAMAS Conference 2019 Conference Paper

Supple: Multiagent Communication Protocols with Causal Types

• Akin Günay
• Amit K. Chopra
• Munindar P. Singh

A (communication) protocol captures how agents collaborate by specifying the messages they exchange. In particular, since the information content of messages characterizes the interactions a protocol specifies, message types can improve collaboration by strengthening the specification of what each agent may legitimately expect from another agent. In addition, in implementations, typing information can enable improved verification of agents. We introduce Supple, a protocol specification language that expresses message schemas with typed parameters. Supple enables definition of causal types for parameters that constrain how other parameters are computed in a protocol enactment. We give the formal semantics of Supple; characterize the liveness and safety of Supple specifications; and provide decision procedures for them.

IJCAI Conference 2019 Conference Paper

The Interplay of Emotions and Norms in Multiagent Systems

• Anup K. Kalia
• Nirav Ajmeri
• Kevin S. Chan
• Jin-Hee Cho
• Sibel Adalı
• Munindar P. Singh

We study how emotions influence norm outcomes in decision-making contexts. Following the literature, we provide baseline Dynamic Bayesian models to capture an agent's two perspectives on a directed norm. Unlike the literature, these models are holistic in that they incorporate not only norm outcomes and emotions but also trust and goals. We obtain data from an empirical study involving game play with respect to the above variables. We provide a step-wise process to discover two new Dynamic Bayesian models based on maximizing log-likelihood scores with respect to the data. We compare the new models with the baseline models to discover new insights into the relevant relationships. Our empirically supported models are thus holistic and characterize how emotions influence norm outcomes better than previous approaches.

AAMAS Conference 2018 Conference Paper

Compositional Correctness in Multiagent Interactions

• Samuel H. Christie V.
• Amit K. Chopra
• Munindar P. Singh

An interaction protocol specifies the constraints on communication between agents in a multiagent system. Ideally, we would like to be able to treat protocols as modules and compose them in a declarative manner to systematically build more complex protocols. Supporting composition correctly requires taking into account informationbased causality relationships between protocols. One important problem that may arise from inadequate consideration of such relationships is that the enactment of a composite protocol may violate atomicity; that is, some components may be initiated but prevented from completing. We use the well-known all or nothing principle as the basis for formalizing atomicity as a novel correctness property for protocols. Our contributions are the following. One, we motivate and formalize atomicity and highlight its distinctiveness from related correctness notions. Two, we give a decision procedure for verifying atomicity and report results from an implementation. For concreteness of exposition and technical development, we adopt BSPL as an exemplar of information causality approaches.

IJCAI Conference 2018 Conference Paper

Robust Norm Emergence by Revealing and Reasoning about Context: Socially Intelligent Agents for Enhancing Privacy

• Nirav Ajmeri
• Hui Guo
• Pradeep K. Murukannaiah
• Munindar P. Singh

Norms describe the social architecture of a society and govern the interactions of its member agents. It may be appropriate for an agent to deviate from a norm; the deviation being indicative of a specialized norm applying under a specific context. Existing approaches for norm emergence assume simplified interactions wherein deviations are negatively sanctioned. We investigate via simulation the benefits of enriched interactions where deviating agents share selected elements of their contexts. We find that as a result (1) the norms are learned better with fewer sanctions, indicating improved social cohesion; and (2) the agents are better able to satisfy their individual goals. These results are robust under societies of varying sizes and characteristics reflecting pragmatic, considerate, and selfish agents.

AAMAS Conference 2017 Conference Paper

Arnor: Modeling Social Intelligence via Norms to Engineer Privacy-Aware Personal Agents

• Nirav Ajmeri
• Pradeep K. Murukannaiah
• Hui Guo
• Munindar P. Singh

We seek to address the challenge of engineering socially intelligent personal agents that are privacy-aware. We propose Arnor, a method, including a metamodel based on social constructs. Arnor incorporates social norms and goes beyond existing agent-oriented software engineering (AOSE) methods by systematically capturing how a personal agent’s actions influence the social experience it delivers. We conduct two empirical studies to evaluate Arnor. First, via a multiphase developer study, we show that Arnor simplifies application development. Second, via simulation experiments, we show that Arnor provides improved privacy-preserving social experience to end users than personal agents engineered using a traditional AOSE method.

AAMAS Conference 2017 Conference Paper

Splee: A Declarative Information-Based Language for Multiagent Interaction Protocols

• Amit K. Chopra
• Samuel H. Christie V.
• Munindar P. Singh

IJCAI Conference 2017 Conference Paper

Tosca: Operationalizing Commitments Over Information Protocols

• Thomas C. King
• Akın Günay
• Amit K. Chopra
• Munindar P. Singh

The notion of commitment is widely studied as a high-level abstraction for modeling multiagent interaction. An important challenge is supporting flexible decentralized enactments of commitment specifications. In this paper, we combine recent advances on specifying commitments and information protocols. Specifically, we contribute Tosca, a technique for automatically synthesizing information protocols from commitment specifications. Our main result is that the synthesized protocols support commitment alignment, which is the idea that agents must make compatible inferences about their commitments despite decentralization.

KER Journal 2016 Journal Article

Classifying sanctions and designing a conceptual sanctioning process model for socio-technical systems

• Luis G. Nardin
• Tina Balke-Visser
• Nirav Ajmeri
• Anup K. Kalia
• Jaime S. Sichman
• Munindar P. Singh

Abstract We understand a socio-technical system (STS) as a cyber-physical system in which two or more autonomous parties interact via or about technical elements, including the parties’ resources and actions. As information technology begins to pervade every corner of human life, STSs are becoming ever more common, and the challenge of governing STSs is becoming increasingly important. We advocate a normative basis for governance, wherein norms represent the standards of correct behaviour that each party in an STS expects from others. A major benefit of focussing on norms is that they provide a socially realistic view of interaction among autonomous parties that abstracts low-level implementation details. Overlaid on norms is the notion of a sanction as a negative or positive reaction to potentially any violation of or compliance with an expectation. Although norms have been well studied as regards governance for STSs, sanctions have not. Our understanding and usage of norms is inadequate for the purposes of governance unless we incorporate a comprehensive representation of sanctions. We address the aforementioned gap by proposing (i) a sanction typology that reflects the relevant features of sanctions, and (ii) a conceptual sanctioning process model providing a functional structure for sanctioning in STS. We demonstrate our contributions via a motivating scenario from the domain of renewable energy trading.

IJCAI Conference 2016 Conference Paper

Coco: Runtime Reasoning about Conflicting Commitments

• Nirav Ajmeri
• Jiaming Jiang
• Rada Chirkova
• Jon Doyle
• Munindar P. Singh

To interact effectively, agents must enter into commitments. What should an agent do when these commitments conflict? We describe Coco, an approach for reasoning about which specific commitments apply to specific parties in light of general types of commitments, specific circumstances, and dominance relations among specific commitments. Coco adapts answer-set programming to identify a maximal set of nondominated commitments. It provides a modeling language and tool geared to support practical applications.

AAMAS Conference 2016 Conference Paper

Custard: Computing Norm States Over Information Stores

• Amit K. Chopra
• Munindar P. Singh

IS Journal 2016 Journal Article

Revani: Revising and Verifying Normative Specifications for Privacy

• Ozgur Kafaly
• Nirav Ajmeri
• Munindar P. Singh

Privacy remains a major challenge today, partly because it brings together social and technical considerations. Yet, current software engineering focuses only on the technical aspects. In contrast, the authors' approach, Revani, understands privacy from the standpoint of sociotechnical systems (STSs), with particular attention on the social elements of STSs. They specify STSs via a combination of technical mechanisms and social norms founded on accountability. Revani provides a way to formally represent mechanisms and norms and applies model checking to verify whether specified mechanisms and norms would satisfy stakeholder requirements. Additionally, Revani provides a set of design patterns and a revision tool to update an STS specification as necessary. The authors demonstrate the work of Revani on a healthcare emergency use case pertaining to patient privacy during disasters.

IJCAI Conference 2016 Conference Paper

Silk: A Simulation Study of Regulating Open Normative Multiagent Systems

• Mehdi Mashayekhi
• Hongying Du
• George F. List
• Munindar P. Singh

In a multiagent system, a (social) norm describes what the agents may expect from each other. Norms promote autonomy (an agent need not comply with a norm) and heterogeneity (a norm describes interactions at a high level independent of implementation details). Researchers have studied norm emergence through social learning where the agents interact repeatedly in a graph structure. In contrast, we consider norm emergence in an open system, where membership can change, and where no predetermined graph structure exists. We propose Silk, a mechanism wherein a generator monitors interactions among member agents and recommends norms to help resolve conflicts. Each member decides on whether to accept or reject a recommended norm. Upon exiting the system, a member passes its experience along to incoming members of the same type. Thus, members develop norms in a hybrid manner to resolve conflicts. We evaluate Silk via simulation in the traffic domain. Our results show that social norms promoting conflict resolution emerge in both moderate and selfish societies via our hybrid mechanism.

IJCAI Conference 2015 Conference Paper

Composing and Verifying Commitment-Based Multiagent Protocols

• Matteo Baldoni
• Cristina Baroglio
• Amit K. Chopra
• Munindar P. Singh

We consider the design and enactment of multiagent protocols that describe collaboration using “normative” or “social” abstractions, specifically, commitments. A (multiagent) protocol defines the relevant social states and how they progress; each participant maintains a local projection of these states and acts accordingly. Protocols expose two important challenges: (1) how to compose them in a way that respects commitments and (2) how to verify the compliance of the parties with the social states. Individually, these challenges are inadequately studied and together not at all. We motivate the notion of a social context to capture how a protocol may be enacted. A protocol can be verifiably enacted when its participants can determine each other’s compliance. We first show the negative result that even when protocols can be verifiably enacted in respective social contexts, their composition cannot be verifiably enacted in the composition of those social contexts. We next show how to expand such a protocol so that it can be verifiably enacted. Our approach involves design rules to specify composite protocols so they would be verifiably enactable. Our approach demonstrates a use of dialectical commitments, which have previously been overlooked in the protocols literature.

IJCAI Conference 2015 Conference Paper

Norms as a Basis for Governing Sociotechnical Systems: Extended Abstract

• Munindar P. Singh

ECAI Conference 2014 Conference Paper

Estimating Trust from Agents' Interactions via Commitments

• Anup K. Kalia
• Zhe Zhang 0004
• Munindar P. Singh

How an agent trusts another naturally depends on the outcomes of their interactions. Previous approaches have treated the outcomes in a domain-specific way. We propose an approach relating trust to the domain-independent notion of commitments. We conduct an empirical study to evaluate our approach, in which subjects read emails extracted from the Enron dataset (augmented with some synthetic emails for completeness), and estimate trust between each pair of communicating participants. We propose a probabilistic model for trust based on commitment outcomes and show how to train its parameters for each subject based on the subject's trust assessments. The results are promising, though imperfect. Our main contribution is to launch a research program into computing trust based on a semantically well-founded account of agent interactions.

JAAMAS Journal 2014 Journal Article

Muon: designing multiagent communication protocols from interaction scenarios

• Anup K. Kalia
• Munindar P. Singh

Abstract Designing a suitable communication protocol is a key challenge in engineering a multiagent system. This paper proposes Muon, an approach that begins from representative samples of interactions or scenarios. Muon identifies key semantic structures and patterns based on (social) commitments to formally analyze the scenarios and offers a methodology for designing protocols that would meet stakeholder needs. Interestingly, Muon applies its formal representations to suggest ways to identify additional scenarios needed to address exceptions arising in the interactions. This paper contributes (1) a conceptual model of message types and causal relationships among them as a foundation for developing commitment-based communication protocols; (2) a robust, reusable characterization of semantic structures reflecting the above model; (3) a mapping from an annotated scenario to causally related interactions; and (4) a methodology to synthesize specifications of communication protocols. This paper reports on an empirical evaluation involving developers creating protocols from two real-life cases.

TIST Journal 2013 Journal Article

Formalizing and verifying protocol refinements

• Scott N. Gerard
• Munindar P. Singh

A (business) protocol describes, in high-level terms, a pattern of communication between two or more participants, specifically via the creation and manipulation of the commitments between them. In this manner, a protocol offers both flexibility and rigor: a participant may communicate in any way it chooses as long as it discharges all of its activated commitments. Protocols thus promise benefits in engineering cross-organizational business processes. However, software engineering using protocols presupposes a formalization of protocols and a notion of the refinement of one protocol by another. Refinement for protocols is both intuitively obvious (e.g., PayViaCheck is clearly a kind of Pay ) and technically nontrivial (e.g., compared to Pay, PayViaCheck involves different participants exchanging different messages). This article formalizes protocols and their refinement. It develops Proton, an analysis tool for protocol specifications that overlays a model checker to compute whether one protocol refines another with respect to a stated mapping. Proton and its underlying theory are evaluated by formalizing several protocols from the literature and verifying all and only the expected refinements.

TIST Journal 2013 Journal Article

Introduction to special section on trust in multiagent systems

• Rino Falcone
• Munindar P. Singh

IJCAI Conference 2013 Conference Paper

Macau: A Basis for Evaluating Reputation Systems

• Christopher J. Hazard
• Munindar P. Singh

Reputation is a crucial concept in dynamic multiagent environments. Despite the large body of work on reputation systems, no metrics exist to directly and quantitatively evaluate and compare them. We present a common conceptual interface for reputation systems and a set of four measurable desiderata that are broadly applicable across multiple domains. These desiderata employ concepts from dynamical systems theory to measure how a reputation system reacts to a strategic agent attempting to maximize its own utility. We study a diverse set of well-known reputation models from the literature in a moral hazard setting and identify a rich variety of characteristics that they support.

TIST Journal 2013 Journal Article

Norms as a basis for governing sociotechnical systems

• Munindar P. Singh

We understand a sociotechnical system as a multistakeholder cyber-physical system. We introduce governance as the administration of such a system by the stakeholders themselves. In this regard, governance is a peer-to-peer notion and contrasts with traditional management, which is a top-down hierarchical notion. Traditionally, there is no computational support for governance and it is achieved through out-of-band interactions among system administrators. Not surprisingly, traditional approaches simply do not scale up to large sociotechnical systems. We develop an approach for governance based on a computational representation of norms in organizations. Our approach is motivated by the Ocean Observatory Initiative, a thirty-year $400 million project, which supports a variety of resources dealing with monitoring and studying the world's oceans. These resources include autonomous underwater vehicles, ocean gliders, buoys, and other instrumentation as well as more traditional computational resources. Our approach has the benefit of directly reflecting stakeholder needs and assuring stakeholders of the correctness of the resulting governance decisions while yielding adaptive resource allocation in the face of changes in both stakeholder needs and physical circumstances.

TIST Journal 2013 Journal Article

Research directions in agent communication

• Amit K. Chopra
• Alexander Artikis
• Jamal Bentahar
• Marco Colombetti
• Frank Dignum
• Nicoletta Fornara
• Andrew J. I. Jones
• Munindar P. Singh

Increasingly, software engineering involves open systems consisting of autonomous and heterogeneous participants or agents who carry out loosely coupled interactions. Accordingly, understanding and specifying communications among agents is a key concern. A focus on ways to formalize meaning distinguishes agent communication from traditional distributed computing: meaning provides a basis for flexible interactions and compliance checking. Over the years, a number of approaches have emerged with some essential and some irrelevant distinctions drawn among them. As agent abstractions gain increasing traction in the software engineering of open systems, it is important to resolve the irrelevant and highlight the essential distinctions, so that future research can be focused in the most productive directions. This article is an outcome of extensive discussions among agent communication researchers, aimed at taking stock of the field and at developing, criticizing, and refining their positions on specific approaches and future challenges. This article serves some important purposes, including identifying (1) points of broad consensus; (2) points where substantive differences remain; and (3) interesting directions of future work.

AAMAS Conference 2011 Conference Paper

Commitments with Regulations: Reasoning about Safety and Control in Regula

• Elisa Marengo
• Matteo Baldoni
• Cristina Baroglio
• Amit K. Chopra
• Viviana Patti
• Munindar P. Singh

Commitments provide a flexible means for specifying the business relationships among autonomous and heterogeneous agents, and lead to a natural way of enacting such relationships. However, current formalizations of commitments incorporate conditions expressed as propositions, but disregard (1) temporal regulations and (2) an agent's control over such regulations. Thus, they cannot handle realistic application scenarios where time and control are often central because of domain conventions or other requirements. We propose a new formalization of commitments that builds on an existing representation of events in which we can naturally express temporal regulations as well as what an agent can control, including indirectly as based on the commitments and capabilities of other agents. Our formalization supports a notion of commitment safety. A benefit of our consolidated approach is that by incorporating these considerations into commitments we enable agents to reason about and flexibly enact the regulations. The main contributions of this paper include (1) a formal semantics of commitments that accommodates temporal regulations; (2) a formal semantics of the notions of innate and social control; and (3) a formalization of when a temporal commitment is safe for its debtor. We evaluate our contributions using an extensive case study.

JAAMAS Journal 2011 Journal Article

Generalized framework for personalized recommendations in agent networks

• Chung-Wei Hang
• Munindar P. Singh

Abstract An agent network can be modeled as a directed weighted graph whose vertices represent agents and edges represent a trust relationship between the agents. This article proposes a new recommendation approach, dubbed L oc P at, which can recommend trustworthy agents to a requester in an agent network. We relate the recommendation problem to the graph similarity problem, and define the similarity measurement as a mutually reinforcing relation. We understand an agent as querying an agent network to which it belongs to generate personalized recommendations. We formulate a query into an agent network as a structure graph applied in a personalized manner that reflects the pattern of relationships centered on the requesting agent. We use this pattern as a basis for recommending an agent or object (a vertex in the graph). By calculating the vertex similarity between the agent network and a structure graph, we can produce a recommendation based on similarity scores that reflect both the link structure and the trust values on the edges. Our resulting approach is generic in that it can capture existing network-based approaches merely through the introduction of appropriate structure graphs. We evaluate different structure graphs with respect to two main kinds of settings, namely, social networks and ratings networks. Our experimental results show that our approach provides personalized and flexible recommendations effectively and efficiently based on local information.

AAMAS Conference 2011 Conference Paper

Information-Driven Interaction-Oriented Programming: BSPL, the Blindingly Simple Protocol Language

• Munindar P. Singh

We present a novel approach to interaction-oriented programming based on declaratively representing communication protocols. Our approach exhibits the following distinguishing features. First, it treats a protocol as an engineering abstraction in its own right. Second, it models a protocol in terms of the information that the protocol needs to proceed (so agents enact it properly) and the information the protocol would produce (when it is enacted). Third, it naturally maps traditional operational constraints to the information needs of protocols, thereby obtaining the desired interactions without additional effort or reasoning. Fourth, our approach naturally supports shared nothing enactments: everything of relevance is included in the communications and no separate global state need be maintained. Fifth, our approach accommodates, but does not require, formal representations of the meanings of the protocols. We evaluate this approach via examples from the literature.

AAMAS Conference 2011 Conference Paper

Kokomo: An Empirically Evaluated Methodology for Affective Applications

• Derek J. Sollenberger
• Munindar P. Singh

The introduction of affect or emotion modeling into software opens up new possibilities for improving user experience. Yet, current techniques for building affective applications are limited, with the treatment of affect in essence handcrafted in each application. The multiagent middleware Koko attempts to reduce the burden of incorporating affect modeling into applications. However, Koko can be effective only if the models it needs to function are suitably constructed. We propose Kokomo, a methodology that employs expressive communicative acts as an organizing principle for affective applications. Kokomo specifies the steps needed to create an affective application in Koko. A key motivation is that Kokomo would facilitate the construction of an affective application by engineers who may lack a prior background in affective modeling. We empirically evaluate Kokomo's utility through a developer study. The results are positive and demonstrate that the developers who used Kokomo were able to develop an affective application in less time, with fewer lines of code, and with a reduced perception of difficulty than developers who worked without Kokomo.

AAMAS Conference 2011 Conference Paper

Specifying and Applying Commitment-Based Business Patterns

• Amit K. Chopra
• Munindar P. Singh

Recent work in communications and business modeling emphasizes a commitment-based view of interaction. By abstracting away from implementation-level details, commitments can potentially enhance perspicuity during modeling and flexibility during enactment. We address the problem of creating commitment-based specifications that directly capture business requirements, yet apply in distributed settings. We encode important business patterns in terms of commitments and group them into methods to better capture business requirements. Our approach yields significant advantages over existing approaches: our patterns (1) respect agent autonomy; (2) capture business intuitions faithfully; and (3) can be enacted in real-life, distributed settings. We evaluate our contributions using the Extended Contract Net Protocol.

AAMAS Conference 2011 Conference Paper

Trust as Dependence: A Logical Approach

• Munindar P. Singh

We propose that the trust an agent places in another agent declaratively captures an architectural connector between the two agents. We formulate trust as a generic modality expressing a relationship between a truster and a trustee. Specifically, trust here is definitionally independent of, albeit constrained by, other relevant modalities such as commitments and beliefs. Trust applies to a variety of attributes of the relationship between truster and trustee. For example, an agent may trust someone to possess an important capability, exercise good judgment, or to intend to help it. Although such varieties of trust are hugely different, they respect common logical patterns. We present a logic of trust that expresses such patterns as reasoning postulates concerning the static representation of trust, its dynamics, and its relationships with teamwork and other agent interactions. In this manner, the proposed logic illustrates the general properties of trust that reflect natural intuitions, and can facilitate the engineering of multiagent systems.

TAAS Journal 2011 Journal Article

Trustworthy Service Selection and Composition

• Chung-Wei Hang
• Munindar P. Singh

We consider Service-Oriented Computing (SOC) environments. Such environments are populated with services that stand proxy for a variety of information resources. A fundamental challenge in SOC is to select and compose services, to support specified user needs directly or by providing additional services. Existing approaches for service selection either fail to capture the dynamic relationships between services or assume that the environment is fully observable. In practical situations, however, consumers are often not aware of how the services are implemented. We propose two distributed trust-aware service selection approaches: one based on Bayesian networks and the other on a beta-mixture model. We experimentally validate our approach through a simulation study. Our results show that both approaches accurately punish and reward services in terms of the qualities they offer, and further that the approaches are effective despite incomplete observations regarding the services under consideration.

TAAS Journal 2010 Journal Article

Evidence-based trust

• Yonghong Wang
• Munindar P. Singh

An evidence-based account of trust is essential for an appropriate treatment of application-level interactions among autonomous and adaptive parties. Key examples include social networks and service-oriented computing. Existing approaches either ignore evidence or only partially address the twin challenges of mapping evidence to trustworthiness and combining trust reports from imperfectly trusted sources. This article develops a mathematically well-formulated approach that naturally supports discounting and combining evidence-based trust reports. This article understands an agent Alice's trust in an agent Bob in terms of Alice's certainty in her belief that Bob is trustworthy. Unlike previous approaches, this article formulates certainty in terms of evidence based on a statistical measure defined over a probability distribution of the probability of positive outcomes. This definition supports important mathematical properties ensuring correct results despite conflicting evidence: (1) for a fixed amount of evidence, certainty increases as conflict in the evidence decreases and (2) for a fixed level of conflict, certainty increases as the amount of evidence increases. Moreover, despite a subtle definition of certainty, this work (3) establishes a bijection between evidence and trust spaces, enabling robust combination of trust reports and (4) provides an efficient algorithm for computing this bijection.

JAAMAS Journal 2010 Journal Article

Koko: an architecture for affect-aware games

• Derek J. Sollenberger
• Munindar P. Singh

Abstract The importance of affect in delivering engaging experiences in entertainment and educational games is well recognized. Yet, current techniques for building affect-aware games are limited, with the maintenance and use of affect in essence being handcrafted for each game. The Koko architecture describes a service-oriented middleware that reduces the burden of incorporating affect recognition into games, thereby enabling developers to concentrate on the functional and creative aspects of their applications. The Koko architecture makes three key contributions: (1) improving developer productivity by creating a reusable and extensible environment; (2) yielding an enhanced user experience by enabling independently developed games and other applications to collaborate and provide a more coherent user experience than currently possible; (3) enabling affective communication in multiplayer and social games. Further, Koko is intended to be used as an extension of existing game architectures. We recognize that complex games require additional third party libraries, such as game engines. To enable the required flexibility we define the interfaces of the Koko architecture in a formal manner, thereby enabling the implementation of those interfaces to readily adapt to the unique requirements of game’s other architectural components and requirements.

AAMAS Conference 2009 Conference Paper

Choice, Interoperability, and Conformance in Interaction Protocols and Service Choreographies

• Matteo Baldoni
• Cristina Baroglio
• Amit K. Chopra
• Nirmit Desai
• Viviana Patti
• Munindar P. Singh

Many real-world applications of multiagent systems require independently designed (heterogeneous) and operated (autonomous) agents to interoperate. We consider agents who offer business services and collaborate in interesting business service engagements. We formalize notions of interoperability and conformance, which appropriately support agent heterogeneity and autonomy. With respect to autonomy, our approach considers the choices that each agent has, and how their choices are coordinated so that at any time one agent leads and its counterpart follows, but with initiative fluidly shifting among the participants. With respect to heterogeneity, we characterize the variations in the agents’ designs, and show how an agent may conform to a specification or substitute for another agent. Our approach addresses a challenging problem with multiparty interactions that existing approaches cannot solve. Further, we introduce a set of edit operations by which to modify an agent design so as to ensure its conformance with others.

AAMAS Conference 2009 Conference Paper

Multiagent Commitment Alignment

• Amit K. Chopra
• Munindar P. Singh

Commitments provide a basis for understanding interactions in multiagent systems. Successful interoperation relies upon the interacting parties being aligned with respect to their commitments. However, alignment is nontrivial in a distributed system where agents communicate asynchronously and make different observations. We propose a formalization for commitments that ensures alignment despite asynchrony. This formalization consists of three elements: (1) a semantics of commitment operations; (2) messaging patterns that implement the commitment operations; and (3) weak constraints on agents’ behaviors to ensure the propagation of vital information. We prove that our formalization ensures alignment. We illustrate the generality of our formalization with several real-life scenarios.

AAMAS Conference 2009 Conference Paper

Operators for Propagating Trust and their Evaluation in Social Networks

• Chung-Wei Hang
• Yonghong Wang
• Munindar P. Singh

AAAI Conference 2008 Conference Paper

Semantical Considerations on Dialectical and Practical Commitments

• Munindar P. Singh

IJCAI Conference 2007 Conference Paper

• Munindar P. Singh

Protocols structure interactions among communicating agents. A commitment machine models a protocol in terms of how the commitments of the various parties evolve. Commitment machines thus support flexible behavior while providing a meaningful basis for compliance with a protocol. Unfortunately, current formulations of commitment machines are not sufficiently general or rigorous.

IJCAI Conference 2007 Conference Paper

• Yonghong Wang
• Munindar P. Singh

Trust should be substantially based on evidence. Further, a key challenge for multiagent systems is how to determine trust based on reports from multiple sources, who might themselves be trusted to varying degrees. Hence an ability to combine evidence-based trust reports in a manner that discounts for imperfect trust in the reporting agents is crucial for multiagent systems. This paper understands trust in terms of belief and certainty: A 's trust in B is reflected in the strength of A 's belief that B is trustworthy. This paper formulates certainty in terms of evidence based on a statistical measure defined over a probability distribution of the probability of positive outcomes. This novel definition supports important mathematical properties, including (1) certainty increases as conflict increases provided the amount of evidence is unchanged, and (2) certainty increases as the amount of evidence increases provided conflict is unchanged. Moreover, despite a more subtle definition than previous approaches, this paper (3) establishes a bijection between evidence and trust spaces, enabling robust combination of trust reports and (4) provides an efficient algorithm for computing this bijection.

AAMAS Conference 2007 Conference Paper

An Event-Driven Approach for Agent-Based Business Process Enactment

• Payal Chakravarty
• Munindar P. Singh

Agents enacting business processes in large open environments need to adaptively accommodate exceptions. Work on multiagent approaches can flexibly model business processes. This paper proposes an event-driven architecture that enriches such models with events resulting in a more robust and proactive system. Specifically, we place this architecture in a business process framework based on protocols and policies, where agents' behaviors are specified via rules. The contributions of this paper include (1) an event-driven architecture, (2) a specification language that combines event logic with rules and (3) a methodology to incorporate events into a process (such as for fine-grained monitoring), (4) a way to manage subscriptions to simple events efficiently. This approach is applied on a well-known business scenario.

AAMAS Conference 2007 Conference Paper

Choice and Interoperation in Protocol Enactment

• Amit K. Chopra
• Munindar P. Singh

Protocols describe interactions among agents and thus underlie the engineering of multiagent systems. However, protocols are enacted by agents in physical systems. In particular, considerations of communication models and how distributed agents are able to make compatible choices would greatly affect whether a protocol may in fact be enacted successfully. The objective of this paper is to study the conceptual underpinnings of protocol enactment in multiagent systems. It seeks to characterize the operationalization of agents so as to determine whether and when agents may be interoperable.

AAMAS Conference 2007 Conference Paper

Dynamics of Contracts-Based Organizations A Formal Approach Based on Institutions

• Yathiraj B. Udupi
• Munindar P. Singh

An organization comprises a group of collaborating agents (individual agents or nested organizations) that exhibit complex behaviors. Of particular interest are dynamic organizations that form and dissolve as their members' needs change. Such organizations are important in many applications, in cluding scientific and business computing. Contracts among autonomous agents have long been used to facilitate their collaboration. This paper provides a contracts-based approach for managing organizations. The proposed approach places organizations within institutions, themselves modeled as specialized organizations. Commitments form the basis of contracts and this paper establishes some important dynamic aspects by providing a commitment life cycle analysis. This approach has been applied in a prototype tool to manage organizations.

AAMAS Conference 2007 Conference Paper

Enacting Protocols by Commitment Concession

• Pinar Yolum
• Munindar P. Singh

Commitment protocols formalize interactions among autonomous, heterogeneous agents, leaving the agents' local policies unspecified. This paper studies the problem of agents enacting commitment protocols, which inherently requires that their policies cohere with the given protocols. Specifically, in many important settings, if agents incautiously create and discharge commitments, they can expose themselves to certain risk; conversely, if the agents are (excessively) cautious, a protocol enactment may deadlock. This paper adopts the well-known idea of monotonic concession, but specializes and enhances it with the particular features of commitments. Specifically, this paper formulates inference rules for commitment concession that respect the nature of commitments. Next, it shows how commitments can be systematically revised as the agents incrementally engage each other in enacting their protocol. This paper demonstrates how such rules can be applied in practice, and identifies conditions under which progress and termination of protocol enactment can be guaranteed.

AAMAS Conference 2007 Conference Paper

InterPol: A Policy Framework for Managing Trust and Privacy in Referral Networks

• Yathiraj B. Udupi
• Munindar P. Singh

Referral networks are a kind of P2P system consisting of autonomous agents who seek, provide services, or refer other service providers. Key applications include service discovery and selection, and knowledge sharing. This use of referrals is inspired by human interactions, where referrals are a key basis for judging the trustworthiness of a given service.

AAMAS Conference 2007 Conference Paper

Toward Verification of Commitment Protocols and their Compositions

• Nirmit Desai
• Zhengang Cheng
• Amit K. Chopra
• Munindar P. Singh

Commitment protocols have been proposed as a basis for modeling and enacting interactions among agents, such as those needed to carry out business processes. A central idea is that protocols would be developed and shared via libraries, and refined and composed to produce protocols that serve specific needs. Success in this program, therefore, presupposes that individual protocols and their compositions can be formally verified with respect to the properties of interest. This paper outlines an approach for verifying the correctness of commitment protocols and their compositions that exploits the well-known software engineering technique of model checking.

JAAMAS Journal 2006 Journal Article

An algebra for commitment protocols

• Ashok U. Mallya
• Munindar P. Singh

Abstract Protocols enable unambiguous, smooth interactions among agents. Commitments among agents are a powerful means of developing protocols. Commitments enable flexible execution of protocols and help agents reason about protocols and plan their actions accordingly, while at the same time providing a basis for compliance checking. Multiagent systems based on commitments can conveniently and effectively model business interactions because the autonomy and heterogeneity of agents mirrors real-world businesses. Such modeling, however, requires multiagent systems to host a rich variety of protocols that can capture the needs of different applications. We show how a commitment-based semantics provides a basis for refining and aggregating protocols. We propose an approach for designing commitment protocols wherein traditional software engineering notions such as refinement and aggregation are extended to apply to protocols. We present an algebra of protocols that can be used to compose protocols by refining and merging existing ones, and does this at a level of abstraction high enough to be useful for real-world applications.

AAMAS Conference 2005 Conference Paper

Agent-Based Trust Model Involving Multiple Qualities

• E. Michael Maximilien
• Munindar P. Singh

AAMAS Conference 2005 Conference Paper

Formalizing and Achieving Multiparty Agreements via Commitments

• Feng Wan
• Munindar P. Singh

AAMAS Conference 2005 Conference Paper

Modeling Exceptions via Commitment Protocols

• Ashok Mallya
• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Commitments and Causality for Multiagent Design

• Feng Wan
• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Detecting deception in reputation management

• Bin Yu
• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Distributed Enactment of Multiagent Workflows

• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Emergent Properties of Referral Systems

• Pinar Yolum
• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Engineering Commitment-Based Multiagent Systems: A Temporal Logic Approach

• Jie Xing
• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Ladders of Success: An Empirical Approach to Trust

• Pinar Yolum
• Munindar P. Singh

AAMAS Conference 2003 Conference Paper

Searching social networks

• Bin Yu
• Munindar P. Singh

AAMAS Conference 2002 Conference Paper

An Evidential Model of Distributed Reputation Management

• Bin Yu
• Munindar P. Singh

AAMAS Conference 2002 Conference Paper

Flexible Protocol Specification and Execution: Applying Event Calculus Planning using Commitments

• Pinar Yolum
• Munindar P. Singh

AILAW Journal 1999 Journal Article

An ontology for commitments in multiagent systems:

• Munindar P. Singh

Social commitments have long been recognized as an important concept for multiagent systems. We propose a rich formulation of social commitments that motivates an architecture for multiagent systems, which we dub spheres of commitment. We identify the key operations on commitments and multiagent systems. We distinguish between explicit and implicit commitments. Multiagent systems, viewed as spheres of commitment (SoComs), provide the context for the different operations on commitments. Armed with the above ideas, we can capture normative concepts such as obligations, taboos, conventions, and pledges as different kinds of commitments. In this manner, we synthesize ideas from multiagent systems, particularly the idea of social context, with ideas from ethics and legal reasoning, specifically that of directed obligations in the Hohfeldian tradition.

IJCAI Conference 1999 Conference Paper

Be Patient and Tolerate Imprecision: How Autonomous Agents can Coordinate Effectively

• Sudhir K. Rustogi
• Munindar P. Singh

ECAI Conference 1998 Conference Paper

The Intentions of Teams: Team Structure, Endodeixis, and Exodeixis

• Munindar P. Singh

ECAI Conference 1992 Conference Paper

A Critical Examination of Use Cohen-Levesque Theory of Intentions

• Munindar P. Singh

ECAI Conference 1992 Conference Paper

Computing the Temporal Structure of Events in Natural Language

• Mona Singh 0002
• Munindar P. Singh

AAAI Conference 1991 Conference Paper

A Logic of Situated Know-How

• Munindar P. Singh

Know-how is an important concept in Artificial Intelligence. It has been argued previously that it cannot be successfully reduced to the knowledge of facts. In this paper, I present sound and complete axiomatizations for two non-reductive and intuitively natural formal definitions of the know-how of an agent situated in a complex environment. I also present some theorems giving useful properties of know-how, and discuss and resolve an interesting paradox (which is described within). This is done using a new operator in the spirit of Dynamic Logic that is introduced herein and whose semantics and proof-theory are given.

ECAI Conference 1990 Conference Paper

Towards a Theory of Situated Know-How

• Munindar P. Singh