crossover probability

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crossover probability

 Hi, I have a question to crossover probability. On JGAP web site we can read that: * *Natural selection in JGAP is statistical, so chromosomes that are more fit have a better statistical chance of being selected over chromosomes that are less fit, but it's not guaranteed. So I assumed, that probability of choosing chromosome to crossover depending on fitness value of this chromosome. But when in studied the CrossOverOperator i have noticed something like that: public void operate(final Population a_population,                      final List a_candidateChromosomes) {    // Work out the number of crossovers that should be performed.    // -----------------------------------------------------------    int size = Math.min(getConfiguration().getPopulationSize(),                        a_population.size());    int numCrossovers = 0;    if (m_crossoverRate >= 0) {      numCrossovers = size / m_crossoverRate;    }    else if (m_crossoverRateCalc != null) {      numCrossovers = size / m_crossoverRateCalc.calculateCurrentRate();    }    else {      numCrossovers = (int) (size * m_crossoverRatePercent);    } Where calculateCurrentRate() return int. So: 1. The fitness value of chromosome does not impact on the probability of choosing this chromosome to crossover right?? The only place where the fitness value is used is in NaturalSelector where we choose "n" best chromosomes, yes? 2. Even if I wrote my own UniversalRateCalc, the rate(probability) of crossover is the same for every chromosome in this evolution, yes? So what should I do if I want that probability of crossover of particular chromosome is an individual value for each chromosome in this population and depends of fitness value of this chromosome? ------------------------------------------------------------------------------ Join us December 9, 2009 for the Red Hat Virtual Experience, a free event focused on virtualization and cloud computing. Attend in-depth sessions from your desk. Your couch. Anywhere. http://p.sf.net/sfu/redhat-sfdev2dev_______________________________________________ jgap-users mailing list [hidden email] https://lists.sourceforge.net/lists/listinfo/jgap-users