Migration, Selection Pressure, and Superlinear Speedups

The choice of migrants and the replacement of individuals are not often considered important parameters of parallel GAs. However, this chapter used two different methods to show that choosing the migrants or replacements according to their fitness increases the selection pressure. Some migration policies may cause the algorithm to converge significantly faster. The migration policy that accelerates convergence the most is to choose both the migrants and the replacements according to their fitness, which is also the most common policy.