Research on Feature Selection Algorithm Based on Natural Evolution Strategy

Feature selection is an NP-hard problem that aims to improve the accuracy of the model by eliminating irrelevant or redundant features to reduce model training time. Therefore, feature selection is an important data preprocessing technique in the fields of machine learning, data mining, and pattern recognition. This study proposes a new feature selection algorithm MCC-NES based on natural evolutionary strategy. Firstly, the algorithm adopts natural evolutionary strategy based on diagonal covariance matrix modeling, which adaptively adjusts parameters through gradient information. Secondly, in order to enable the algorithm to effectively deal with feature selection problems, a feature coding mechanism is introduced in the initialization phase, and combined with classification accuracy and dimensional reduction, given the new fitness function. In addition, the idea of sub-population cooperative co-evolution is introduced to solve high-dimensional data. The original problem is decomposed into relatively small sub-problems to reduce the combined effect of the original problem scale and each sub-question is solved independently, and then all sub-problems are correlated to optimize the solution to the original problem. Further, applying multiple competing evolutionary populations to enhance the exploration ability of the algorithm and designing a population restart strategy to prevent the population from falling into the local optimal solution. Finally, the proposed algorithm is compared with several traditional feature selection algorithms on some UCI public datasets. The experimental results show that the proposed algorithm can effectively complete the feature selection problem and has excellent performance compared with the classical feature selection algorithm, especially when dealing with high-dimensional data. © Copyright 2020, Institute of Software, the Chinese Academy of Sciences. All rights reserved.