Partial constraint satisfaction

Abstract

A constraint satisfaction problem involves finding values for variables subject to constraints on which combinations of values are allowed. In some cases it may be impossible or impractical to solve these problems completely. We may seek to partially solve the problem in an optimal or sufficient sense. A formal model is presented for defining and studying such partial constraint satisfaction problems. The basic components of this model are a constraint satisfaction problem, a problem space, and a metric on that space. Algorithms for solving partial constraint satisfaction problems are discussed. A specific branch and bound algorithm is described. Some initial experimental experience with this algorithm is presented.