Catálogo de publicaciones - libros

In highly regulated environments, where a set of norms defines accepted behaviour, protocols provide a way to reduce complexity by giving direct, step by step guidelines for behaviour, as long as the protocols comply with the norms. In this work we propose a formal framework to design a protocol from a normative specification. In order to be able to connect (descriptive) norms with (operational) protocols, an intermediate level is created by the use of landmarks.

Design by contract is a well known theory that views software construction as based on contracts between clients (callers) and suppliers (routines), relying on mutual obligations and benefits made explicit by assertions. However, there is a gap between this theory and software engineering concepts and tools. For example, dealing with contract violations is realized by exception handlers, whereas it has been observed in the area of deontic logic in computer science that violations and exceptions are distinct concepts that should not be confused. To bridge this gap, we propose a software design language based on temporal deontic logic. Moreover, we show how preferences over the possible outcomes of a supplier can be added. We also discuss the relation between the normative stance toward systems implicit in the design by contract approach and the intentional or BDI stance popular in agent theory.

A norm-governed agent takes social norms into account in its practical reasoning. Such norms characterise its role within a specific organisational context. By adopting a role, the agent commits to fulfil and adhere to the social norms associated with that role. These commitments require the agent to act in a way that does not violate any of its prohibitions or obligations. In adopting different sets of norms, an agent may experience conflicts between these norms as well as inconsistencies between possible actions for fulfilling its obligations and its currently adopted set of norms. In order to resolve such problems, it must be informed about conflicts and inconsistencies. The NoA architecture for norm-governed agents implements a computationally efficient mechanism for identifying and indicating such problems – possible candidates for action are assigned a specific label that contains cross-referenced information of actions and norms. As actions are indicated as problematic and not simply filtered out, the agent can still choose to either act according to its norms or against them. The labelling mechanism presented in this paper is therefore a critical step towards enabling an agent to reason about norm violations – the agent becomes norm-autonomous.

In this paper we introduce organizations and roles in Shoham and Tennenholtz’ artificial social systems, using a normative system. We model how real agents determine the behavior of organizations by playing roles in the organization, and how the organization controls the behavior of agents playing a role in it. We consider the design of an organization in terms of roles and the assignment of agents to roles, and the evolution of organizations. We do not present a complete formalization of the computational problems, but we illustrate our approach by examples.

Reorganization of the structure of an organization is a crucial issue in multi-agent systems that operate in an open, dynamic environment. Ideally, autonomous agents must be able to evaluate and decide the most appropriate organization given the environment conditions. That is, there is a need for dynamic reorganization of coordination structures. In this paper, we describe how simulation studies could help to determine whether and how reorganization should take place, and present a simulation scenario that can be used to evaluate the congruence, or fit, between organizational structure and task performance. Preliminary results using a simulation environment illustrate how one can explore triggers for reorganization and compare strategies.

There is a wide agreement on the use of norms in order to specify the expected behaviour of agents in open MAS. However, in highly regulated domains, where norms dictate what can and cannot be done, it can be hard to determine whether a desired goal can actually be achieved without violating the norms. To help the agents in this process, agents can make use of predefined (knowledge-based) protocols, which are designed to help reach a goal without violating any of the norms. But how can we guarantee that these protocols are actually norm-compliant? Can these protocols really realise results without violating the norms? In this paper we introduce a formal method, based on program verification, for checking the norm compliance of (knowledge-based) protocols.

This paper proposes a rule language for defining social expectations based on a metric interval temporal logic with past and future modalities and a current-time binding operator. An algorithm for run-time monitoring compliance of rules in this language based on formula progression is also presented.