Article

Hyperequivalence of logic programs with respect to supported models.

Annals of Mathematics and Artificial Intelligence (Impact Factor: 0.2). 01/2008; 53:331-365. DOI: 10.1007/s10472-009-9119-8
Source: DBLP

ABSTRACT Recent research in nonmonotonic logic programming has focused on certain types of program equivalence, which we refer to here
as hyperequivalence, that are relevant for program optimization and modular programming. So far, most results concern hyperequivalence relative
to the stable-model semantics. However, other semantics for logic programs are also of interest, especially the semantics
of supported models which, when properly generalized, is closely related to the autoepistemic logic of Moore. In this paper,
we consider a family of hyperequivalence relations for programs based on the semantics of supported and supported minimal models. We characterize these relations
in model-theoretic terms. We use the characterizations to derive complexity results concerning testing whether two programs
are hyperequivalent relative to supported and supported minimal models.

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Miroslaw Truszczynski