Constructing Free Energy Approximations and Generalized Belief Propagation Algorithms
|MERL Report: ||TR2002-35: Jonathan S. Yedidia, William T. Freeman, and Yair Weiss
Note: This technical report is superseded by MERL TR2004-040, available at http://www.merl.com/papers/TR2004-040/.The region graph method is the most general of these methods, and it subsumes all the other methods. Region graphs also provide the natural graphical setting for GBP algorithms. We explain how to obtain three different versions of GBP algorithms and show that their fixed points will always correspond to stationary points of the region graph approximation to the free energy. We also show that the region graph approximation is exact when the region graph has no cycles.