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below). Like with mutation, the gap between average and best fitness increases
with transposition rate. Also worth pointing out is that populations are evolv-
ing more efficiently at
p
ris
= 1.0 (
Ps
= 82%) than at
p
is
= 1.0 (
Ps
= 62%). Con-
sequently, the gap between average and best fitness is smaller in the last case
(compare plots
c
and
f
). More generally, the plots for average fitness obtained
for RIS transposition occupy lower positions than the corresponding IS dy-
namics. As previously shown, for healthy populations, this is an indicator of a
more efficient evolution. Indeed, as shown in Figure 12.1, RIS transposition
performs slightly better than IS transposition.
a.
Ps
= 46%
b.
Ps
= 77%
c.
Ps
= 82%
200
200
200
175
175
175
150
150
150
125
125
125
100
100
100
75
75
75
50
50
50
25
25
25
0
0
0
0 0 0 0 0 0
Generations
0 0 0 0 0 0
Generations
0 0 0 0 0 0
Generations
d.
Ps
= 42%
e.
Ps
= 72%
f.
Ps
= 62%
200
200
200
175
175
175
150
150
150
125
125
125
100
100
100
75
75
75
50
50
50
25
25
25
0
0
0
0 0 0 0 0 0
Generations
0 0 0 0 0 0
Generations
0 0 0 0 0 0
Generations
Figure 12.3.
Evolutionary dynamics characteristic of populations evolving by
RIS transposition (plots
a
,
b
, and
c
) and IS transposition (plots
d
,
e
, and
f
). The
success rate above each plot was determined in the experiment of Figure 12.1.
a)
p
ris
= 0.2.
b)
p
ris
= 0.6.
c)
p
ris
= 1.0.
d)
p
is
= 0.2.
e)
p
is
= 0.6.
f)
p
is
= 1.0. Notice
that the evolutionary behavior is similar to mutation (see Figure 12.2) and very
different from recombination (see Figure 12.4 below). Note also that the plots for
average fitness obtained for RIS transposition occupy lower positions than the
corresponding IS dynamics, an indicator of a more tumultuous and, in this case,
more efficient evolution.
