# EVOLVED PREAMBLES FOR MAX-SAT HEURISTICS

### Luís O. Rigo Jr., Valmir C. Barbosa

#### Abstract

MAX-SAT heuristics normally operate from random initial truth assignments to the variables. We consider the use of what we call preambles, which are sequences of variables with corresponding single-variable assignment actions intended to be used to determine a more suitable initial truth assignment for a given problem instance and a given heuristic. For a number of well established MAX-SAT heuristics and benchmark instances, we demonstrate that preambles can be evolved by a genetic algorithm such that the heuristics are outperformed in a significant fraction of the cases. The heuristics we consider include the well-known novelty, walksat-tabu, and adaptnovelty+. Our benchmark instances are those of the 2004 SAT competition and those of the 2008 MAX-SAT evaluation.

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#### Paper Citation

#### in Harvard Style

O. Rigo Jr. L. and C. Barbosa V. (2011). **EVOLVED PREAMBLES FOR MAX-SAT HEURISTICS** . In *Proceedings of the International Conference on Evolutionary Computation Theory and Applications - Volume 1: ECTA, (IJCCI 2011)* ISBN 978-989-8425-83-6, pages 23-31. DOI: 10.5220/0003660400230031

#### in Bibtex Style

@conference{ecta11,

author={Luís O. Rigo Jr. and Valmir C. Barbosa},

title={EVOLVED PREAMBLES FOR MAX-SAT HEURISTICS},

booktitle={Proceedings of the International Conference on Evolutionary Computation Theory and Applications - Volume 1: ECTA, (IJCCI 2011)},

year={2011},

pages={23-31},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003660400230031},

isbn={978-989-8425-83-6},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the International Conference on Evolutionary Computation Theory and Applications - Volume 1: ECTA, (IJCCI 2011)

TI - EVOLVED PREAMBLES FOR MAX-SAT HEURISTICS

SN - 978-989-8425-83-6

AU - O. Rigo Jr. L.

AU - C. Barbosa V.

PY - 2011

SP - 23

EP - 31

DO - 10.5220/0003660400230031