I am a bit confused. I haven't seen the usage of "likelihood" in setting the probability of performing crossover/mutation. The following is what I learned from the tutorials and what I continue using: pop.subpop.0.species.pipe = ec.breed.MultiBreedingPipeline # Koza's decision here was odd... pop.subpop.0.species.pipe.generate-max = false # Subsidiary pipelines: pop.subpop.0.species.pipe.num-sources = 2 pop.subpop.0.species.pipe.source.0 = ec.gp.koza.CrossoverPipeline pop.subpop.0.species.pipe.source.0.prob = 0.9 pop.subpop.0.species.pipe.source.1 = ec.breed.ReproductionPipeline pop.subpop.0.species.pipe.source.1.prob = 0.1 I searched a little for the parameter "likelihood", and this is what I found in class BreedingPipeline: public static final java.lang.String *P_LIKELIHOOD* Indicates the probability that the Breeding Pipeline will perform its mutative action instead of just doing reproduction. Not sure what this does, but I guess it is for normal EC and can be ignored in a GP process. I could be totally wrong. On Mon, Mar 3, 2014 at 7:14 AM, Francisco Lopez de la Franca < [log in to unmask]> wrote: > Hi again. > I've used gp.koza.xover.likelihood to set the probability of performing > the crossover operator and I've seen differences in my results, what it > sounds good. > After checking the koza.params file, I see that like for xover, there is a > gp.koza.mutate param. I've tried with gp.koza.mutate.likelihood and when > printing unaccessed params, the gp.koza.mutate.likelihood appears in that > list. > > Please, how do I set a probability for performing the mutation operator, I > mean, with probability 0.x I want the mutation operation to be performed? > > Thank you very much. > My best regards. > > > 2014-03-01 1:02 GMT+01:00 Francisco Lopez de la Franca < > [log in to unmask]>: > > Sorry for the troubles, but I've re-read the manual several times and it >> doesnīt clarify my question. >> In genetic algorithms, evolution strategies, etc, it is specified a >> probability of doing recombination, and another one of doing mutation. And, >> I want to do the same for genetic programming, an I donīt see the way to do >> it in ECJ. >> Thank you anyway. >> Regards. >> >> >> 2014-02-28 14:35 GMT+01:00 Sean Luke <[log in to unmask]>: >> >> I think you need to read up on parameter bases in ECJ. See the manual's >>> section on parameters and parameter databases. >>> >>> Sean >>> >>> On Feb 28, 2014, at 2:26 AM, Francisco Lopez de la Franca < >>> [log in to unmask]> wrote: >>> >>> > I want to specify the probability of performing mutation and the same >>> for crossover. How do I specify it for each operator? >>> > I've seen the following parameters and I don`t know which one to use: >>> > >>> > <Bass>.likelihood >>> > pop.subpop.0.species.pipe.source.0.prob >>> > gp.koza.xover.prob >>> > pop.subpop.0.species.mutation-prob >>> > pop.subpop.0.species.crossover-prob >>> > >>> > Additionally, I'd like to know the type of mutation and crossover >>> applied in the run. How do I know them? >>> > >>> > Thanks a lot. >>> > >>> > >>> > 2014-02-27 15:22 GMT+01:00 Sean Luke <[log in to unmask]>: >>> > If you want to specify the probability whether a given operator >>> performs mutation (say) or just copies parents and returns them, the >>> parameter you're looking for is 'likelihood'. >>> > >>> > If you want to specify the probability of doing mutation type 1 versus >>> mutation type 2 versus crossover or whatever, the tool you want is called >>> ec.breed.MultiBreedingPipeline. >>> > >>> > Sean >>> > >>> > On Feb 27, 2014, at 6:50 AM, Francisco Lopez de la Franca < >>> [log in to unmask]> wrote: >>> > >>> > > Hi. >>> > > >>> > > I'd like to know how it's specified in the params file the >>> probability of carrying out the recombination and mutation in genetic >>> programming. (I think recombination is called in GP crossover, isn't it?). >>> > > >>> > > Thanks. >>> > >>> >> >> >