The EM algorithm that works on shared BDDs with negative edges

Abstract

We extend the BDD-EM algorithm, which is an expectation-maximization (EM) algorithm working on binary decision diagrams (BDDs), for shared BDDs (SBDDs) with negative edges. BDDs are used as a compact expression of Boolean formulas and moreover the use of SBDDs and negative edges is expected to reduce the time and space in the case where we have some similar partial structures. We show that the proposed algorithm which utilizes SBDD with negative edges for bipartite noisy-OR network reduces time and space in executing the EM algorithm.