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Extremal optimization for optimizing kernel function and its parameters in support vector regression

The performance of the support vector regression (SVR) model is sensitive to the kernel type and its parameters. The determination of an appropriate kernel type and the associated parameters for SVR is a challenging research topic in the field of support vector learning. In this study, we present a novel method for simultaneous optimization of the SVR kernel function and its parameters, formulated as a mixed integer optimization problem and solved using the recently proposed heuristic ‘extremal optimization (EO)’. We present the problem formulation for the optimization of the SVR kernel and parameters, the EO-SVR algorithm, and experimental tests with five benchmark regression problems. The results of comparison with other traditional approaches show that the proposed EO-SVR method provides better generalization performance by successfully identifying the optimal SVR kernel function and its parameters.