Longer-Term Memory in Clause Weighting Local Search for SAT

نویسندگان

  • Valnir Ferreira
  • John Thornton
چکیده

This paper presents a comparative study between a state-ofthe-art clause weighting local search method for satisfiability testing and a variant modified to obtain longer-term memory from a global measure of clause perturbation. We present empirical evidence indicating that by learning which clauses are hardest to satisfy, the modified method can offer significant performance improvements for a well-known range of satisfiable problems. We conclude that our method’s ability to learn, and consequently to offer performance improvement, can be attributed to its ability to obtain information from a global measure of hardness, rather than from the contextual perspective exploited in previous works.

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تاریخ انتشار 2004