Integrating and Sampling Cuts in Bounded Treewidth Graphs
نویسندگان
چکیده
In this paper, we consider the problem of evaluating (s, t)-cuts in a bounded treewidth graph. In particular, we show how to compute the partition function for weighted cuts of the graph, i.e., the total weight of all (s, t)-cuts where the weight of a single cut is the product of its edge weights. This method can also easily be adapted to work with additive weights for the cost of a cut. We also present a method for sampling a cut proportional to its weight in linear time. Computing the partition function is #P-hard for general graphs, and our sampling algorithm is simple enough to prove useful is several application areas. Finally, we discuss an alternative method for sampling cuts that uses Markov chains and show that, in the worst case, its mixDepartment of Computer Science, Rochester Institute of Technology Rochester, NY 14623, USA
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