Computer Science Department
School of Computer Science, Carnegie Mellon University


Using Optimal Dependency-Trees for Combinatorial Optimization: Learning the Structure of the Search Space

Shumeet Baluja*, Scott Davies

January 1997

Keywords: Combinatorial optimization, dependency trees, probability models, bayesian networks

Many combinatorial optimization algorithms have no mechanism to capture inter-parameter dependencies. However, modeling such dependencies may allow an algorithm to concentrate its sampling more effectively on regions of the search space which have appeared promising in the past. We present an algorithm which incrementally learns second-order probability distributions from good solutions seen so far, uses these statistics to generate optimal (in terms of maximum likelihood) dependency trees to model these distributions, and then stochastically generates new candidate solutions from these trees. We test this algorithm on a variety of optimization problems. Our results indicate superior performance over other tested algorithms that either (1) do not explicitly use these dependencies, or (2) use these dependencies to generate a more restricted class of dependency graphs.

20 pages

*Justsystem Pittsburgh Research Center, 4616 Henry Street, Pittsburgh, PA 15213

Return to: SCS Technical Report Collection
School of Computer Science homepage

This page maintained by