The Puzzle of the Persistent Question Marks : A Case Study of Genetic Drift

In an important paper Hinton and Nowlan demonstrate the Baldwin e ect in a simple Genetic Algorithm The ability of the phenotype to adapt coupled with the evolu tionary process allows behavioural goals to become over time genetically speci ed this seems Lamarckian but is not In that paper as a subsidiary point the slowness of xa tion of the last few goals is commented on and a later paper by Belew attempts an analysis In this paper I show that ge netic drift is the explanation for this slowness phenomenon Using a di usion equation ap proach I give an analysis of genetic drift for genetic algorithms where it is too often ig nored Critical relationships between muta tion rate population size and forces of selec tion are given which decide whether genetic drift will be of signi cance or not