Join tree propagation with prioritized messages

Current join tree propagation algorithms treat all propagated messages as being of equal importance. On the contrary, it is often the case in real‐world Bayesian networks that only some of the messages propagated from one join tree node to another are relevant to subsequent message construction at the receiving node. In this article, we propose the first join tree propagation algorithm that identifies and constructs the relevant messages first. Our approach assigns lower priority to the irrelevant messages as they only need to be constructed so that posterior probabilities can be computed when propagation terminates. Experimental results, involving the processing of evidence in four real‐world Bayesian networks, empirically demonstrate an improvement over the state‐of‐the‐art method for exact inference in discrete Bayesian networks. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010