Rank
Linear-rank selection: an alternate selection operator. The population is ranked best-to-worst (using the solver's GeneticAlgorithmSolver.compare, i.e. the minimization sense of the penalized objective). Each individual receives a selection probability that depends only on its rank, not on the magnitude of its fitness, which makes the operator robust to objective scale and sign. With selectionPressure s in [1,2], the best individual (rank 0) has probability s/n and the worst (rank n-1) has probability (2-s)/n; parents are then drawn by roulette over these probabilities. s = 1 gives uniform selection; s = 2 gives the strongest pressure (the worst individual gets probability 0).
Parameters
the linear-ranking selection pressure, in [1,2]. The default is defaultSelectionPressure.