The ACM Journal of Experimental Algorithmics |
The Reactive Search (RS) method proposes the integration of a simple history-based feedback scheme into local search for the on-line determination of free parameters. In this paper a new RS algorithm is proposed for the approximated solution of the Maximum Satisfiability problem: a component based on local search with temporary prohibitions is complemented with a reactive scheme that determines ("learns") the appropriate value of the prohibition parameter by monitoring the Hamming distance along the search trajectory (algorithm H-RTS). In addition, the non-oblivious functions recently introduced in the framework of approximation algorithms are used to discover a better local optimum in the initial part of the search. The algorithm is developed in two phases. First the bias-diversification properties of individual candidate components are analyzed by extensive empirical evaluation, then a reactive scheme is added to the winning component, based on Tabu Search. The final tests on a benchmark of random Max-3Sat and Max-4Sat problems demonstrate the superiority of H-RTS with respect to alternative heuristics.
| Received |
Revised |
Accepted |
Final Revision |
Published |
| June 28, 1996 |
February 7, 1997 |
March 11, 1997 |
April 19, 1997 |
May 19, 1997 |
Last updated and validated May 19, 1997, by editor@jea.acm.org