Improving Performance in Combinatorial Optimisation Using Averaging and Clustering

  • Mohamed Qasem
  • Adam Prügel-Bennett
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5482)


In a recent paper an algorithm for solving MAX-SAT was proposed which worked by clustering good solutions and restarting the search from the closest feasible solutions. This was shown to be an extremely effective search strategy, substantially out-performing traditional optimisation techniques. In this paper we extend those ideas to a second classic NP-Hard problem, namely Vertex Cover. Again the algorithm appears to provide an advantage over more established search algorithms, although it shows different characteristics to MAX-SAT. We argue this is due to the different large-scale landscape structure of the two problems.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Mohamed Qasem
    • 1
  • Adam Prügel-Bennett
    • 1
  1. 1.School of Electronics and Computer ScienceUniversity of SouthamptonUK

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