Catálogo de publicaciones - libros

Trust and reputation mechanisms are commonly used to infer expectations of future behaviour from past interactions. They are of particular relevance when agents have to choose appropriate counterparts for their interactions as it may also happen within virtual organisations. However, when agents join an organisation, information about past interactions is usually not available. The use of organisational structures can tackle this problem and can improve the efficiency of trust and reputation mechanisms by endowing agents with some extra information to choose the best agents to interact with. In this context, we present how certain structural properties of virtual organisations can be used to build an efficient trust model in a local way. Furthermore, we introduce a testbed (TOAST) that allows to analyse different trust and reputation models in situations where agents act within virtual organisations. We experimentally evaluate our approach and show its validity.

We study the problem of checking the competence of communicative agents operating in a global society in order to receive and offer electronic services. Such a society will be composed of local sub-societies that will often be semi-open, viz., entrance of agents in a semi-open society is conditional to specific admission criteria. Assuming that a candidate agent provides an abstract description of their communicative skills, we present a test that a controller agent could perform in order to decide if a candidate agent should be admitted. We formulate this test by revisiting an existing knowledge representation framework based on games specified as extended logic programs. The resulting framework finds useful application in complex and inter-operable web-services construed as semi-open societies in support of the global vision known as the Semantic Web.