In the context of using norms for controlling multiagent systems, a vitally important question that has not yet been addressed in the literature is the development of mechanisms for monitoring norm compliance under partial action observability. This paper proposes the reconstruction of unobserved actions to tackle this problem. In particular, we formalize the problem of reconstructing unobserved actions, and propose an information model and algorithms for monitoring norms under partial action observability using two different processes for reconstructing unobserved actions. Our evaluation shows that reconstructing unobserved actions increases significantly the number of norm violations and fulfilments detected.
Regarding , several authors proposed developing entities at the infrastructure level that are in charge of both monitoring and enforcing norms. Cardoso & Oliveira @cite_25 proposed an architecture in which the monitoring and enforcement of norms is made by a single institutional entity. This centralized implementation represents a performance limitation when dealing with a considerable number of agents. To address the performance limitation of centralized approaches, distributed mechanisms for an institutional enforcement of norms were proposed in @cite_21 @cite_16 @cite_18 @cite_6 .
@cite_18 @cite_21 @cite_6 @cite_16 @cite_25
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The behaviours of autonomous agents may deviate from those deemed to be for the good of the societ al systems of which they are a part. Norms have therefore been proposed as a means to regulate agent behaviours in open and dynamic systems, where these norms specify the obliged, permitted and prohibited behaviours of agents. Regulation can effectively be achieved through use of enforcement mechanisms that result in a net loss of utility for an agent in cases where the agent's behaviour fails to comply with the norms. Recognition of compliance is thus crucial for achieving regulation. In this paper we propose a generic architecture for observation of agent behaviours, and recognition of these behaviours as constituting, or counting as, compliance or violation. The architecture deploys monitors that receive inputs from observers, and processes these inputs together with transition network representations of individual norms. In this way, monitors determine the fulfillment or violation status of norms. The paper also describes a proof of concept implementation and deployment of monitors in electronic contracting environments. Software technology is undergoing a transition form monolithic systems, constructed according to a single overall design, into conglomerates of semiautonomous, heterogeneous, and independently designed subsystems, constructed and managed by different organizations, with little, if any, knowledge of each other. Among the problems inherent in such conglomerates, none is more serious than the difficulty to control the activities of the disparate agents operating in it, and the difficulty for such agents to coordinate their activities with each other. We argue that the nature of coordination and control required for such systems calls for the following principles to be satisfied: (1) coordination policies need to be enforced: (2) the enforcement needs to be decentralized; and (3) coordination policies need to be formulated explicitly—rather than being implicit in the code of the agents involved—and they should be enforced by means of a generic, broad spectrum mechanism; and (4) it should be possible to deploy and enforce a policy incrementally, without exacting any cost from agents and activities not subject to it. We describe a mechansim called law-governed interaction (LGI), currently implemented by the Moses toolkit, which has been designed to satisfy these principles. We show that LGI is at least as general as a conventional centralized coordination mechanism (CCM), and that it is more scalable, and generally more efficient, then CCM. Norms have been promoted as a coordination mechanism for controlling agent behaviours in open MAS. Thus, agent platforms must provide normative support, allowing both norm-aware and non norm-aware agents to take part in MAS controlled by norms. In this paper, the most relevant proposals on the definition of norm enforcement mechanisms have been analysed. These proposals present several drawbacks that make them unsuitable for open MAS. In response to these problems, this paper describes a new Norm-Enforcing Architecture aimed at controlling open MAS. Norms are widely recognised as a means of coordinating multiagent systems. The distributed management of norms is a challenging issue and we observe a lack of truly distributed computational realisations of normative models. In order to regulate the behaviour of autonomous agents that take part in multiple, related activities, we propose a normative model, the Normative Structure (NS), an artifact that is based on the propagation of normative positions (obligations, prohibitions, permissions), as consequences of agents' actions. Within a NS, conflicts may arise due to the dynamic nature of the MAS and the concurrency of agents' actions. However, ensuring conflict-freedom of a NS at design time is computationally intractable. We show this by formalising the notion of conflict, providing a mapping of NSs into Coloured Petri Nets and borrowing well-known theoretical results from that field. Since online conflict resolution is required, we present a tractable algorithm to be employed distributedly. We then demonstrate that this algorithm is paramount for the distributed enactment of a NS. Norms and institutions have been proposed to regulate multi-agent interactions. However, agents are intrinsically autonomous, and may thus decide whether to comply with norms. On the other hand, besides institutional norms, agents may adopt new norms by establishing commitments with other agents. In this paper, we address these issues by considering an electronic institution that monitors the compliance to norms in an evolving normative framework: norms are used both to regulate an existing environment and to define contracts that make agents' commitments explicit. In particular, we consider the creation of virtual organizations in which agents commit to certain cooperation efforts regulated by appropriate norms. The supervision of norm fulfillment is based on the notion of institutional reality, which is constructed by assigning powers to agents enacting institutional roles. Constitutive rules make a connection between the illocutions of those agents and institutional facts, certifying the occurrence of ...