A Machine-Learning Approach to Select Important Variables for Recombination on Many-objective Evolutionary Optimization

  • Miyako Sagawa Shinshu University
  • Hernan Aguirre Shinshu University
  • Fabio Daolio Shinshu University
  • Arnaud Liefooghe University of Lille
  • Bilel Derbel University of Lille
  • Sebastien Verel University of the Littoral Opal Coast
  • Kiyoshi Tanaka Shinshu University
Keywords: Evolutionary computation, Machine learning, Multi-objective optimization, Many-objective optimization, Variable selection, Random forest


There exist numerous many-objective real-world optimization problems in various application domains for which it is difficult or time-consuming to derive Pareto optimal solutions. In an evolutionary algorithm, variation operators such as recombination and mutation are extremely important to obtain an effective solution search. In this paper, we study a machine learning-enhanced recombination that incorporates an intelligent variable selection method. The method is based on the importance of variables with respect to the ranking of solutions in objective space that express convergence to the Pareto front. We verify the performance of the enhanced recombination on benchmark test problems with three or more objectives using the many-objective evolutionary algorithm AεSεH as a baseline algorithm. Our experimental analysis reveals that variable importance can effectively enhance the performance of many-objective evolutionary algorithms.


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