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bond 7 in Dw (between positions 23 and 24). Then the following chromosome
is obtained:
01234567890123456
7890123456789012
3456
DTQaababaabbaabba
2637547866481750
7682
Note that the transposon is deleted at the place of origin, maintaining the
domain length and gene integrity.
Suppose now that the arrays below represent the weights and the thresh-
olds of both chromosomes:
W = {-1.64, -1.834, -0.295, 1.205, -0.807, 0.856, 1.702, -1.026, -0.417, -1.061}
T = {-1.14, 1.177, -1.179, -0.74, 0.393, 1.135, -0.625, 1.643, -0.029, -1.639}
As you can see by their expression in Figure 10.2, they encode very different
solutions because the weights are moved around and new combinations of
weights and thresholds are tested.
10.2.3 Intragenic Two-point Recombination
Intragenic two-point recombination was created in order to allow the modifi-
cation of a particular gene without interfering with the other sub-NNs en-
coded in the other genes. The mechanism of this kind of recombination is
exactly the same as in the already familiar two-point recombination of the
basic gene expression algorithm, with the difference that now the recombi-
nation points are chosen within a particular gene.
Consider the following parent chromosomes composed of two genes, each
with a Dw domain (W
i,j
represents the weights of gene
j
in chromosome
i
):
W
0,0
= {-0.78, -0.521, -1.224, 1.891, 0.554, 1.237, -0.444, 0.472, 1.012, 0.679}
W
0,1
= {-1.553, 1.425, -1.606, -0.487, 1.255, -0.253, -1.91, 1.427, -0.103, -1.625}
0123456789012345601234567890123456
TTababaab55239341QDbabbabb40396369
-[0]
Qaabbbabb29127879QDbabbaaa36972318-[1]
W
1,0
= {-0.148, 1.83, -0.503, -1.786, 0.313, -0.302, 0.768, -0.947, 1.487, 0.075}
W
1,1
= {-0.256, -0.026, 1.874, 1.488, -0.8, -0.804, 0.039, -0.957, 0.462, 1.677}
Suppose that gene 0 was chosen to recombine and that point 1 (between
positions 0 and 1) and point 12 (between positions 11 and 12) were chosen as
recombination points. Then the following offspring is formed:
