Beefy Boxes and Bandwidth Generously Provided by pair Networks
Do you know where your variables are?
 
PerlMonks  

Re: Genetic Programming or breeding Perls

by kwilliams (Sexton)
on May 24, 2001 at 19:22 UTC ( #82949=note: print w/ replies, xml ) Need Help??


in reply to Re: Genetic Programming or breeding Perls
in thread Genetic Programming or breeding Perls

I disagree. Fitness is a combination of the individual abilities and the constraints of the environment. If you put an individual in a different environment its fitness for that environment will change.


Comment on Re: Genetic Programming or breeding Perls
Re: Re: Genetic Programming or breeding Perls
by t'mo (Pilgrim) on May 25, 2001 at 02:06 UTC

    Yes, fitness is related to the environment. But...

    In this case, if the algorighm becomes simpler if FITNESS is more tightly associated with the INDIVIDUAL. For example, this:

    sub choose { my $self = shift; my $f = rand(1.0); my $index = 0; my $sum = 0.0; foreach my $fitnes (@{$self->{FITNESSES}}) { $sum += $fitnes; return ${$self->{INDIVIDUALS}}[$index] if $sum >= $f; ++$index; } die "can't select an individual"; }

    becomes:

    sub choose { my $self = shift; my $f = rand(1.0); my $sum = 0.0; foreach my $individual (@{$self->{INDIVIDUALS}}) { $sum += $individual->{FITNESS}; return $individual if $sum >= $f; } die "can't select an individual"; }

    which I consider an improvement, not only due to the fact that there's (a little) less code, but the concept of choosing an individual and not a fitness is emphasized.

    Finally, I must admit that I have a bias in relation to the idea you presented. Yes, environment does determine fitness. However, what if you're trying to evolved generalized behavior, i.e., a program that will perform well in any environment, and not simply the one's it was trained in? The little bit of work I've done with GP has been focused in the direction of trying to avoid such "over-training" or specialization.

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://82949]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others studying the Monastery: (7)
As of 2014-09-22 06:54 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    How do you remember the number of days in each month?











    Results (182 votes), past polls