SOTEA: Population structure, coevolution and diversity maintenance

Last Friday’s talk was about the work of Whitacre and coathors presented in:

• The Self-Organization of Interaction Networks for Nature-Inspired Optimization (Quite related with our research line on population structures (i.e. [1,2]), keeping some similarities with this paper)

The authors propose an EA (called SOTEA) for the sake of diversity maintenance. To this aim, they focus on a self-organized population structure with the shape of a complex network. The network co-evolves with the EA by following two rules (from which emerge a power law population structure):

1. Reproduction rule:

When a new offspring is created, SOTEA add a new node, this node is linked to its parent (asexual reproduction). The parent’s connections are inherited by the offspring with certain probability Padd. Besides, all inherited connections are lost by the parent with probability Premove.

2. Competition rule

A random selected individual competes with its less fit neighbour. From such a competition, the loser results killed and the winner inherits all its connections.

Within the paper, the results are compared versus a Cellular GA and a Panmictic GA. They show that SOTEA keeps better the population diversity than its competitors and converges reasonably to a solution.

Quite a nice work, although I missed a larger and more stressing test suit case (Authors just use the NK landscape test function).