Rar!Ïs ß?t -z:¹#<œv;0 tese.txt°³ôUAt each generation, each individual in the current population is assigned a score (or fitness value), as evaluated by the objective function. The selection function then chooses the parents of the next offspring, according to these scores. The composition of the new population is determined by two parameters: 1) the number of elite children, which are, by definition, the best individuals in the current population which are to survive intact onto the next population, and 2) the crossover fraction, which is the fraction of the new population that is to be generated by crossing over parents from the current population. Mathematically, if n is the size of the population, x is the number of elite children and a is the crossover fraction, then the number of crossover children, y, isÄ={@