Roulette Wheel, aka Wheel of Fortune, belongs to Fitness-Proportionate Selection, one of the several selection methods for selecting new population in genetic algorithms. This method favors the few super fit individuals over the majority. So if a few chromosomes possess overly large fitness values as compared to the majority, they will be selected too often. The consequence is too-quick and pre-mature convergence, resulting in sub-optimal solution. Read my article
Genetic Algorithms Demystified[
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