Reputation-based trust evaluations through diversity

Trust and reputation are signicant components in open dynamic systems for making informed and reliable decisions. State-of-the-art trust models that exploit reputational evidence generally rely on reports from as many sources as possible. Situations exist, however, where seeking evidence from all possible sources is unrealistic. This is particularly the case in resource-constrained environments where querying information sources is costly, for instance in terms of time and bandwidth. This paper describes an approach that exploits diversity among information sources in order to select a small number of candidates to query for reputational evidence. We demonstrate that reliable decisions can be reached using evidence from small groups of individuals. We show that our approach is robust in contexts of variable trust in reputational sources and to a degree of deception.