Journal of Logic and Computation Advance Access originally published online on February 3, 2009
Journal of Logic and Computation 2009 19(2):405-423; doi:10.1093/logcom/exn100
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Original Articles |
Updating Epistemic Logic Programs*
Intelligent Systems Laboratory, School of Computing & Mathematics, University of Western Sydney, Penrith South DC, NSW 1797, Australia
E-mail: yan{at}scm.uws.edu.au
Received 28 February 2008.
| Abstract |
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We consider the problem of updating non-monotonic knowledge bases represented by epistemic logic programs where disjunctive information and notions of knowledge and belief can be explicitly expressed. We propose a formulation for epistemic logic program update based on a principle called minimal change and maximal coherence. The central feature of our approach is that during an update or a sequence of updates, contradictory information is removed on a basis of minimal change under the semantics of epistemic logic programs and then coherent information is maximally retained in the update result. Through various update scenarios, we show that our approach provides both semantic and syntactic characterizations for an update problem. We also investigate essential semantic properties of epistemic logic program update.
Keywords: Epistemic logic programs; non-monotonic reasoning; update
*A preliminary version of this article was published in IJCAI-2003 [24].