Inverse Entailment in
Nonmonotonic Logic Programs

Chiaki Sakama

Department of Computer and Communication Sciences
Wakayama University
Sakaedani, Wakayama 640 8510, Japan
sakama@sys.wakayama-u.ac.jp
http://www.sys.wakayama-u.ac.jp/~sakama



Abstract. Inverse entailment (IE) is known as a technique for finding
inductive hypotheses in Horn theories. When a background theory is
nonmonotonic, however, LB is not applicable in its present form. The
purpose of this paper is extending the JE technique to nonmonotonic
inductive logic programming (ILP). To this end, we first establish a new
entailment theorem in normal logic programs, then introduce the notion
of contrapositive programs. Finally, a theory of IE in nonmonotonic JLP
is constructed.
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