Winning the PASCAL 2011 MAP Challenge with Enhanced AND / OR Branch-and-Bound

This paper describes our entry for the MAP/MPE track of the PA SC L 2011 Probabilistic Inference Challenge, which placed first in al l three time limit categories, 20 seconds, 20 minutes, and 1 hour. Our baseline is a b ranch-and-bound algorithm that explores the AND/OR context-minimal search graph of a graphical model guided by a mini-bucket heuristic. Augmented with rec ent advances that convert the algorithm into an anytime scheme, that improve t he heuristic power via cost-shifting schemes, and using enhanced variable ord ering schemes, it constitutes one of the most powerful MAP/MPE inference methods t date.