About: Evolution window

It was observed in evolution strategies that significant progress toward the fitness/objective function's optimum, generally, can only happen in a narrow band of the mutation step size σ. That narrow band is called evolution window. There are three well-known methods to adapt the mutation step size σ in evolution strategies: * (1/5-th) Success Rule * Self-Adaptation (for example through log-normal mutations) * Cumulative Step Size Adaptation (CSA) On simple functions all of them have been empirically shown to keep the step size within the evolution window.