Belief Revision of Logic Programs Under Answer Set Semantics

The authors have addressed the problem of belief revision in logic programming under the answer set semantics. The approach is based on a monotonic characterisation of logic programs, given in terms of the set of SE models of a program. Based on the latter, they defined and examined operators for logic program expansion and revision. As well as giving properties of these operators, they also considered the complexity and an encoding scheme for revision. This paper is novel, in that it addresses belief change in terms familiar to researchers in belief revision: expansion is characterised in terms of intersections of models, and revision is characterized in terms of minimal distance between models. While they considered set-containment-based revision here, cardinality-based revision can be defined also.