Multi-parental extension of the unimodal normal distribution crossover for real-coded genetic algorithms

The unimodal normal distribution crossover (UNDX) for the real-coded genetic algorithms (RCGA) proposed by Ono et al. (1997, 1998) shows an excellent performance in optimization problems of multi-modal and highly epistatic fitness functions in continuous search space. Further, theoretical analysis of the UNDX shows that the UNDX is a crossover operator that preserves the statistics such as the mean vector and the covariance matrix of the population well. The present paper proposes some design guidelines for crossover operators for RCGA. Then, based on these guidelines, a multi-parental extension of the UNDX is proposed so as to enhance its exploration ability. Performance of the extended UNDX is evaluated by numerical experiments.