Competing hypotheses and abductive inference

This paper explores the nature of competition between hypotheses and the effect of failing to model this relationship correctly when performing abductive inference. In terms of the nature of competition, the importance of the interplay between direct and indirect pathways, where the latter depends on the evidence under consideration, is investigated. Experimental results show that models which treat hypotheses as mutually exclusive or independent perform well in an abduction problem that requires identifying the most probable hypothesis, provided there is at least some positive degree of competition between the hypotheses. However, even in such cases a significant limitation of these models is their inability to identify a second hypothesis that may well also be true.