Robust search procedures are a central component in the design of black-box constraint-programming solvers. This paper proposes activity-based search which uses the activity of variables during propagation to guide the search. Activity-based search was compared experimentally to impact-based search and the wdeg heuristics but not to solution counting heuristics. Experimental results on a variety of benchmarks show that activity-based search is more robust than other heuristics and may produce significant improvements in performance.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Laurent Michel
    • 1
  • Pascal Van Hentenryck
    • 2
  1. 1.University of ConnecticutStorrsUSA
  2. 2.Optimization Research Group, NICTA, Victoria Research LaboratoryThe University of MelbourneAustralia

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