Genetic Algorithm fitness value

hello...

what fitness value is needed in GA optimization? the highest fitness? or the lowest fitness? or the best fitness?

I,m using MATLAB optimization tool for my GA problem, on the "plot function" option, I checked "best fitness".... when I started the optimization, it show "best fitness" and "mean fitness" , both of them has the same value...why is that?

on what condition this "best fitness" is?

thank you and sorry for my bad english

[Vahidreza]

In genetic algorithm, highest is desirable.

Answer 1

[Alan Weiss]

As stated in the documentation, GA attempts to find a minimum of the fitness function.

As stated in the documentation, best fitness means the lowest fitness function among all members in the population. Mean fitness is the average over all members in the current population. If you have the same value for best and mean, then your population has little diversity, or your fitness function returns the same value for all members of the population.

Good luck,

Alan Weiss

MATLAB mathematical toolbox documentation