Showing papers by "Michael J. Maher published in 2010"
TL;DR: This article provides a compact presentation of the defeasible logic variants, and derives an inclusion theorem which shows that different notions of provability in defeasable logic form a chain of levels of proof.
Abstract: Defeasible reasoning is a computationally simple nonmonotonic reasoning approach that has attracted significant theoretical and practical attention. It comprises a family of logics that capture different intuitions, among them ambiguity propagation versus ambiguity blocking, and the adoption or rejection of team defeat. This article provides a compact presentation of the defeasible logic variants, and derives an inclusion theorem which shows that different notions of provability in defeasible logic form a chain of levels of proof.
48 citations
01 Jan 2010
TL;DR: A general formulation of decomposition-based soft constraints is introduced and it is established that the tightest contractible approximation cannot be expressed in edit-based terms, in general.
Abstract: We study contractibility and its approximation for two very general classes of soft global constraints. We introduce a general formulation of decomposition-based soft constraints and provide a sufficient condition for contractibility and an approach to approximation. For edit-based soft constraints, we establish that the tightest contractible approximation cannot be expressed in edit-based terms, in general.
3 citations
10 Oct 2010
TL;DR: A defeasible logic FDL is defined based on Fordh's logic, and in doing so some similarities and differences between Ford's logic and existing defeasibility logics are identified.
Abstract: Ford has introduced a non-monotonic logic, System LS, inspired by an empirical study of human non-monotonic reasoning. We define here a defeasible logic FDL based on Fordh's logic, and in doing so identify some similarities and differences between Ford's logic and existing defeasible logics. Several technical results about FDL are established, including its inference strength in relation to other defeasible logics.
1 citations