Consistency and Plausible Reasoning
نویسنده
چکیده
The usual approach to p laus ib le reasoning is to associate a v a l i d i t y measure wi th each fac t or r u l e , and to compute from these a v a l i d i t y measure for any deduction tha t is made. This approach is shown to be inappropr iate for some classes of problems, p a r t i c u l a r l y those in which the evidence is not i n t e r n a l l y cons is tent . Two current p laus ib le reasoning arch i tec tures are summarized and each appl ied to the same small task. An analysis of the performance of these systems reveals de f ic ienc ies in each case. The paper then ou t l i nes a new approach based on the discovery of consistent subsets of the given evidence. This system can be used e i the r in i s o l a t i o n or in conjunct ion wi th a va l id i t y -p ropaga t ing a rch i tec tu re . Comparative resu l t s from implementations of a l l three systems are presented.
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