Ensuring Building Block Growth

Abstract

In the previous chapter, we examined estimates of the population size required to ensure that building blocks of the required size are present in the initial population. This chapter develops the theory to permit us to design GAs and choose their parameters to ensure that the market share of the best building blocks grows. We start by reexamining the well-known schema theorem and consider its implications in GA design, both early and late during the life of a run. These considerations help us both qualitatively in choosing appropriate selection operators and quantitatively in setting an appropriate balance between selection pressure and recombination frequency.