An operational approach to norms in artificial institutions

The notion of artificial institution is crucial for the specification of open and dynamic interaction frameworks where heterogeneous and autonomous agents can interact to face problems in various fields, like for instance electronic commerce, business-to-business (B2B) applications, and personal assistant applications. In our view the specification of artificial institutions requires a clear standard definition of some basic concepts: the notion of ontology, authorizations, conventions, and norms. In this paper we propose an operational approach to the definition of norms that is mainly based on the generation of commitments. These norms can be employed to verify if the interacting agents are behaving in accordance with the normative specification of the system. In particular we regard norms as event-driven rules that are fired by events happening in the system and then modify commitments affecting the agents having a certain role. We will discuss the crucial differences between the notion of authorization and permission and how the notion of permissions, obligations, and prohibitions can be expressed in our model. We will investigate the connections among the specification of different artificial institutions, in particular how an institution can enrich or further regulate the entities defined in another one. Finally we will briefly present the specification of the Dutch Auction Institution and of the Auction House Institution in order to exemplify the model presented in this paper

Constraint rule-based programming of norms for electronic institutions

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Organization of Multi-Agent Systems: An Overview

In complex, open, and heterogeneous environments, agents must be able to reorganize towards the most appropriate organizations to adapt unpredictable environment changes within Multi-Agent Systems (MAS). Types of reorganization can be seen from two different levels. The individual agents level (micro-level) in which an agent changes its behaviors and interactions with other agents to adapt its local environment. And the organizational level (macro-level) in which the whole system changes it structure by adding or removing agents. This chapter is dedicated to overview different aspects of what is called MAS Organization including its motivations, paradigms, models, and techniques adopted for statically or dynamically organizing agents in MAS.Comment: 12 page

Extending the Carrel system to mediate in the organ and tissue allocation processes: a first approach

In this paper we extend the formalization of Carrel, a virtual organization for the procurement of tissues for transplantation purposes, in order to model also the procurement of human organs for transplants. We will focus in the organ allocation process to show how it can be formalized with the ISLANDER formalism. Also we present a first mechanism to federate the institution in several geographically-distributed platforms.Postprint (published version

Agent communication and artificial institutions

In this paper we propose an application-independent model for the definition of artificial institutions that can be used to define open multi-agent systems. Such a model of institutional reality makes us able also to define an objective and external semantics of a commitment-based Agent Communication Language (ACL). In particular we propose to regard an ACL as a set of conventions to act on a fragment of institutional reality, defined in the context of an artificial institution. Another contribution of the work presented in this paper is an operational definition of norms, a crucial component of artificial institutions. In fact in open systems interacting agents might not conform to the specifications. We regard norms as event-driven rules that when are fired by events happening in the system create or cancel a set of commitments. An interesting aspect of our proposal is that both the definition of the ACL and the definition of norms are based on the same notion of commitment. Therefore an agent capable of reasoning on commitments can reason on the semantics of communicative acts and on the system of norm

Cooperation, Norms, and Revolutions: A Unified Game-Theoretical Approach

Cooperation is of utmost importance to society as a whole, but is often challenged by individual self-interests. While game theory has studied this problem extensively, there is little work on interactions within and across groups with different preferences or beliefs. Yet, people from different social or cultural backgrounds often meet and interact. This can yield conflict, since behavior that is considered cooperative by one population might be perceived as non-cooperative from the viewpoint of another. To understand the dynamics and outcome of the competitive interactions within and between groups, we study game-dynamical replicator equations for multiple populations with incompatible interests and different power (be this due to different population sizes, material resources, social capital, or other factors). These equations allow us to address various important questions: For example, can cooperation in the prisoner's dilemma be promoted, when two interacting groups have different preferences? Under what conditions can costly punishment, or other mechanisms, foster the evolution of norms? When does cooperation fail, leading to antagonistic behavior, conflict, or even revolutions? And what incentives are needed to reach peaceful agreements between groups with conflicting interests? Our detailed quantitative analysis reveals a large variety of interesting results, which are relevant for society, law and economics, and have implications for the evolution of language and culture as well

Detection and resolution of normative conflicts in multi-agent systems : a literature survey

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Artificial institutions: a model of institutional reality for open multiagent systems

Software agents’ ability to interact within different open systems, designed by different groups, presupposes an agreement on an unambiguous definition of a set of concepts, used to describe the context of the interaction and the communication language the agents can use. Agents’ interactions ought to allow for reliable expectations on the possible evolution of the system; however, in open systems interacting agents may not conform to predefined specifications. A possible solution is to define interaction environments including a normative component, with suitable rules to regulate the behaviour of agents. To tackle this problem, we propose an application-independent model of artificial institutions that can be used to define open multiagent systems. With respect to other approaches to artificial (or electronic) institutions, which mainly focus on the definition of the normative component of open systems, our proposal has a wider scope, in that we model the social context of the interaction, define the semantics of an Agent Communication Language to operate on such a context, and give an operational definition of the norms that are necessary to constrain the agents’ actions. In particular, we define the semantics of a library of communicative acts in terms of operations on agents’ social reality, more specifically on commitments, and regard norms as event-driven rules that, when fired by events happening in the system, create or modify a set of commitments. An interesting aspect of our proposal is that both the definition of the ACL and the definition of norms are based on the same notion of commitment. Therefore an agent capable of reasoning on commitments can reason both on the semantics of communicative acts and on the normative system

Artificial institutions: a model of institutional reality for open multiagent systems

Software agents' ability to interact within different open systems, designed by different groups, presupposes an agreement on an unambiguous definition of a set of concepts, used to describe the context of the interaction and the communication language the agents can use. Agents' interactions ought to allow for reliable expectations on the possible evolution of the system; however, in open systems interacting agents may not conform to predefined specifications. A possible solution is to define interaction environments including a normative component, with suitable rules to regulate the behaviour of agents. To tackle this problem we propose an application-independent metamodel of artificial institutions that can be used to define open multiagent systems. In our view an artificial institution is made up by an ontology that models the social context of the interaction, a set of authorizations to act on the institutional context, a set of linguistic conventions for the performance of institutional actions and a system of norms that are necessary to constrain the agents' action