Identifying Knots of Trust in Virtual Communities

  • Nurit Gal-Oz
  • Ran Yahalom
  • Ehud Gudes
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT, volume 358)

Abstract

Knots of trust are groups of community members having overall “strong” trust relations between them. In previous work we introduced the knot aware trust based reputation model. According to this model, in order to provide a member with reputation information relative to her viewpoint, the system must identify the knot to which that member belongs and interpret its reputation data correctly. In the current paper we present the problem of identifying knots which is modeled as a graph clustering problem, where vertices correspond to individuals and edges describe trust relationships between them. We propose a new perspective for clustering that reflects the subjective idea of trust and the nature of the community. A class of weight functions is suggested for assigning edge weights and their impact on the stability and strength of knots is demonstrated. Finally we show the efficiency of knots of high quality for providing their members with relevant reputation information.

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Copyright information

© International Federation for Information Processing 2011

Authors and Affiliations

  • Nurit Gal-Oz
    • 1
  • Ran Yahalom
    • 1
  • Ehud Gudes
    • 1
  1. 1.Deutsche Telekom LaboratoriesBen-Gurion UniversityBeer-ShevaIsrael

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