Weighted abduction for plan ascription

  • Douglas E. Appelt
  • Martha E. Pollack


We describe an approach to abductive reasoning calledweighted abduction, which uses inference weights to compare competing explanations for observed behavior. We present an algorithm for computing a weighted-abductive explanation, and sketch a model-theoretic semantics for weighted abduction. We argue that this approach is well suited to problems of reasoning about mental state. In particular, we show how the model of plan ascription developed by Konolige and Pollack can be recast in the framework of weighted abduction, and we discuss the potential advantages and disadvantages of this encoding.

Key words

Plan recognition Plan evaluation Mental-state ascription Abduction Evaluation metrics 


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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • Douglas E. Appelt
    • 1
    • 2
  • Martha E. Pollack
    • 1
    • 2
  1. 1.Artificial Intelligence CenterMenlo ParkUSA
  2. 2.Center for the Study of Language and InformationSRI InternationalMenlo ParkUSA

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