Exploiting Variable Dependency in Local Search
نویسندگان
چکیده
Stochastic search has recently been shown to be successful for solving large boolean satissability problems. However, systematic methods tend to be more eeective in problem domains with a large number of dependent variables: that is, variables whose truth values are directly determined by a smaller set of independent variables. In systematic search, truth values can be ee-ciently propagated from the independent to the dependent variables by unit propagation. Such propagation is more expensive in traditional stochastic procedures. In this paper we propose a mechanism for eeectively dealing with dependent variables in stochastic search. We also provide empirical data showing the procedure outperforms the best previous stochastic and systematic search procedures on large formulas with a high ratio of dependent to independent variables.
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تاریخ انتشار 1997