**4. Experimental results and discussion**

To evaluate the performance of the proposed algorithm CA-IM, a comparison of various tests with Distributed Genetic Algorithms utilizing the same knapsack problems was carried out. To make a comparison two kinds of algorithms based in Distributed GAs (Aguirre et al., 2000): (i) A Distributed canonical GA (denoted as DGA), and (ii) a Distributed GA-SRM (denoted as DGA-SRM) were utilized. The SRM term means "Self-Reproduction with Mutation", and introduces diversity by means of mutation inducing the appearance of beneficial mutations.

For the CA-IM algorithm there are two versions: CA-IM\_1 and CA-IM\_2. The only difference is that CA-IM\_1 has a fixed rate for mutation and recombination, while CA-IM\_2 has a random rate for mutation and recombination. The standard CA (CAs) is the Cultural Algorithm with single population.
