2 Other Forms of Lineage Selection

Other implementations of lineage selection could allow further control of genetic diversity via genetic lineages. Here, two other selection schemes are described that could be used with genetic lineages to accomplish different objectives.

• Select $T$ random individuals from within a random lineage to make a tournament. Now selection gives each lineage an equal chance of participating in recombination. This form of selection promotes the combining of individuals that are from different lineages. A potential drawback is the selection of poor quality lineages where no individuals have high fitness. Thus, it would seem necessary to add a bias toward selecting more highly-fit lineages, or those with a high average fitness.
• Select $2 \times T$ random individuals from within a random lineage to make two tournaments, one for each parent in recombination. This form of selection promotes the recombination of genetically similar individuals and could be likened to a form of hill-climbing within a lineage. Assigning a bias toward more fit lineages, ensuring that lineages have a sufficient number of individuals to perform two tournaments and closely observing the convergence within lineages are areas that may need to be addressed within this form of selection.

These three methods, the one used here and the two above, modify the standard tournament selection scheme to force competition and breeding across lineages, force competition within lineages but breeding across lineages, and finally to force competition and breeding from within the same lineage. The more restrictive the method becomes, the more the algorithm will need to consider the potential drawbacks. However, particularly with the last method, these forms of selection could be considered very efficient implementations of more familiar models of similar and dissimilar mate selection and distributed models.

Table 5.1: Experiment and problem parameters for the lineage selection experiments.

Functions
Ant	if_food_ahead, progn2
Parity	and, or, nand, nor
Binomial-3	+, -, *, p/
Terminals
Ant	left, right, move
Parity	D1, D2, D3, D4, D5
Binomial-3	x, ERCs
ERC range	$[-10,10]$
Maximum generations	101