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genetic-algorithmspace-complexityevolutionary-algorithm

Impact of DNA length on Genetic Algorithm performance


I've tried to research about this but couldn't find a satisfying answer. How does the length of an individuals DNA impact on the overall performance of the GA?

Imagine that I'm trying to find a solution for a combinatorial problem with many dimensions (x, y, z, w) for example. Representing the DNA in binary would yield a very long sequence.. are there any suggestions to how far I am allowed to go?

In my opinion the search space (should) increase exponentially with the amount of elements exposed to mutation, am I wrong?

What are some guidelines or techniques (preferably derived from experience) that somebody could provide on how to reduce the length of the DNA?


Solution

  • The GA specific operations such as crossover and mutation should not take long time even for very large chromosome sizes, since they are computationally simple operations (clone a matrix, change a bit of a matrix, etc).

    Most of the time (I have seen around 85-95%) will be spent running the evaluation function for your individuals. Is entirely up to the specific problem you are solving to determine if a large DNA will impact the performance or not. Also, depending on the problem you try to solve, it may be impossible to shorten the size of the possible results.