Evolution Strategies with Multi-parent Recombination

Abstract

This paper experimentally investigates the effect of recombination operators on multirecombinant Evolution Strategies ((μ/μ, λ)-ES). For ES, each individual has a pair of real-valued vectors, i.e., object parameters and strategy parameters. We adopt two popular recombination operators, namely Intermediate Recombination (IR) and Discrete Recombination (DR), and apply IR or DR to both object parameters and strategy parameters. Computer simulations are conducted using three types of (μ/μ, λ)-ES, which are Classical-ES (CES), Fast-ES (FES) and Robust-ES (RES). We show the advantages of IR or DR in CES, FES and RES. Especially, DR on a pair of an object parameters and a strategy parameters improves the performance of all ESs in our experi-ments. By means of principal components analysis of evolutionary dynamics, we discuss the characteristics of (μ/μ, λ)-ES.