Surrogate-Assisted Multi-objective Genetic Algorithms for Fuzzy Rule-Based Classification

Abstract

In this paper, we present a surrogate-assisted multi-objective genetic algorithm to mine a small number of linguistically interpretable fuzzy rules for high-dimensional classification task in the realm of data mining. However, the difficulties like (1) handling of high-dimensional problems by fuzzy rule-based systems (i.e., the exponential increase in the number of fuzzy rules with the number of input variables), (2) the deterioration in the comprehensibility of fuzzy rules when they involve many antecedent conditions, and (3) the optimization of multiple objectives in fuzzy rule-based system may stand as pertinent issues. Hence, to combat with the aforesaid issues, we design the problem as a combinatorial optimization problem with three objectives: to maximize the number of correctly classified training patterns, minimize the number of fuzzy rules, and minimize the total number of antecedent conditions. We optimize these objectives of the fuzzy rule-based system by using a multi-objective genetic algorithm. Further to reduce the number of required evaluations to approximate the Pareto front of computationally expensive multi-objective genetic algorithm for fuzzy rule-based system, a radial basis neural network surrogate model is adapted. This approach searches for non-dominated rule sets with respect to these three objectives. The performance of the surrogate-assisted model is evaluated through a few benchmark datasets obtained from knowledge extraction based on evolutionary learning data repository. The experimental outcome confirm that this model is competitive compared to the non-surrogate-assisted model. However, the performance of the model has drawn a clear edge over rule mining approaches like Decision Table, JRip, OneR, PART, and ZeroR.