Using Four Cost Measures to Determine Arc Reversal Orderings

Four cost measures s1, s2, s3, s4 were recently studied for sorting the operations in Lazy propagation with arc reversal (LPAR), a join tree propagation approach to Bayesian network inference. It has been suggested to use s1 with LPAR, since there is an effectiveness ranking, say s1, s2, s3, s4, when applied in isolation. In this paper, we also suggest to use s1 with LPAR, but to use s2 to break s1 ties, s3 to break s2 ties, and s4 to break s3 ties. Experimental results show that sometimes there is a noticeable gain to be made.