Preference-based flexible multiobjective evolutionary algorithms

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2008
Karahan, İbrahim
In this study,we develop an elitist multiobjective evolutionary algorithm for approximating the Pareto-optimal frontiers of multiobjective optimization problems. The algorithm converges the true Pareto-optimal frontier while keeping the solutions in the population well-spread over the frontier. Diversity of the solutions is maintained by the territory dening property of the algorithm rather than using an explicit diversity preservation mechanism. This leads to substantial computational eciency. We test the algorithm on commonly used test problems and compare its performance against well-known benchmark algorithms. In addition to approximating the entire Pareto-optimal frontier,we develop a preference incorporation mechanism to guide the search towards the decision maker’s regions of interest. Based on this mechanism, we implement two variants of the algorithm. The rst gathers all preference information before the optimization stage to nd approximations of the desired regions. The second one is an interactive algorithm that focuses on the desired region by interacting with the decision maker during the solution process. Based on tests on 2- and 3-objective problems, we observe that both algorithms converge to the preferred regions.

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Citation Formats
İ. Karahan, “Preference-based flexible multiobjective evolutionary algorithms,” M.S. - Master of Science, Middle East Technical University, 2008.