Stochastic Hillclimbing as a Baseline Mathod for Evaluating Genetic Algorithms

We investigate the e ectiveness of stochastic hillclimbing as a baseline for evaluating the performance of genetic algorithms (GAs) as combinatorial function optimizers. In particular, we address four problems to which GAs have been applied in the literature: the maximumcut problem, Koza's 11-multiplexer problem, MDAP (the Multiprocessor Document Allocation Problem), and the jobshop problem. We demonstrate that simple stochastic hillclimbing methods are able to achieve results comparable or superior to those obtained by the GAs designed to address these four problems. We further illustrate, in the case of the jobshop problem, how insights obtained in the formulation of a stochastic hillclimbing algorithm can lead to improvements in the encoding used by a GA. Department of Computer Science, University of California at Berkeley. Supported by a NASA Graduate Fellowship. This paper was written while the author was a visiting researcher at the Ecole Normale Sup erieure{rue d'Ulm, Groupe de BioInformatique, France. E-mail: [email protected] Department of Mathematics, University of California at Berkeley. Supported by an NDSEG Graduate Fellowship. E-mail: [email protected]