(continued from GP update 20150813)
I see 4 ways to deal with the premature convergence:
a) Take a pill.
b) If any given tree falls below the user-defined number of nodes (node count, not depth count), that tree is forced to mutate over and over again ’till it is at or above the prescribed node count. This feels convoluted, as this is not how it happens in the biological world.
c) Nudge the fitness function (higher or lower, depending upon max or min function) such that a tree whose node count is below the user-defined number is less likely to be selected in a Tournament.
d) Simply block any tree whose node count is lower than the user-defined number from entering a tournament. As all four of my mutation types are channelled through tournament selection, this is an easy, 2 line solution.
Is it real-world? Is it any different than applying a maximum depth?
Hmmmm …
(resolved in Kepler’s Law resolved by GP!)