When the Plus Strategy Outperforms the Comma Strategyand When Not
Jens Jägersküpper, Tobias Storch · 2007
Occasionally there have been long debates on whether to use elitist selection or not. In the present paper the simple (1, lambda) EA and {1 + lambda) EA operating on {0, l}nare compared by means of a rigorous runtime analysis. It turns out that only values for lambda that are logarithmic in n are interesting. An illustrative function is presented for which newly developed proof methods show that the (1, lambda) EA - where lambda is logarithmic in n - outperforms the (1 + lambda) EA for any lambda. For smaller offspring populations the (1, lambda) EA is inefficient on every function with a unique optimum, whereas for larger lambda the two randomized search heuristics behave almost equivalently.