Journal of Logic, Language and Information

, Volume 10, Issue 2, pp 183–209 | Cite as

Belief Fusion: Aggregating Pedigreed Belief States

  • Pedrito Maynard-ReidII
  • Yoav Shoham


We introduce a new operator – belief fusion– which aggregates the beliefs of two agents, each informed by a subset of sources ranked by reliability. In the process we definepedigreed belief states, which enrich standard belief states with the source of each piece of information. We note that the fusion operator satisfies the invariants of idempotence, associativity, and commutativity. As a result, it can be iterated without difficulty. We also define belief diffusion; whereas fusion generally produces a belief state with more information than is possessed by either of its two arguments, diffusion produces a state with less information. Fusion and diffusion are symmetric operators, and together define a distributive lattice. Finally, we show that AGM revision can be viewed as fusion between a novice and an expert.

belief aggregation knowledge representation multi-agent systems 


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Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • Pedrito Maynard-ReidII
    • 1
  • Yoav Shoham
    • 1
  1. 1.Computer Science DepartmentStanford UniversityStanfordU.S.A.

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