Intercausal Reasoning with Uninstantiated Ancestor Nodes
نویسندگان
چکیده
Intercausal reasoning is a common inference pattern involving probabilistic dependence of causes of an observed common effect. The sign of this dependence is captured by a qual itative property called product synergy. The current definition of product synergy is insuf ficient for intercausal reasoning where there are additional uninstantiated causes of the common effect. We propose a new definition of product synergy and prove its adequacy for intercausal reasoning with direct and indirect evidence for the common effect. The new def inition is based on a new property matrix half positive semi-definiteness, a weakened form of matrix positive semi-definiteness.
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