A Fixpoint Characterization of Abductive Logic Programs
Katsumi Inoue and Chiaki Sakama
Journal of Logic Programming 27:107-136, North-Holland, 1996.
A new fixpoint semantics for abductive logic programs is provided,
in which the belief models of an abductive program
are characterized as the fixpoint of a disjunctive program obtained
by a suitable program transformation.
In the transformation, both negative hypotheses through negation as failure
and positive hypotheses from the abducibles are dealt with uniformly.
The result is further generalized to a fixpoint semantics for
abductive extended disjunctive programs.
These characterizations allow us to have a parallel bottom-up
model generation procedure for computing abductive explanations from any
(range-restricted and function-free)
normal, extended, and disjunctive programs with integrity constraints.
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