6.2.3. Learning of the imitation parameters
“Sometimes our intentions are not responsible for our possibilities”
—Nadia Bazlova
For these experiments, we created five prey animats with initial values of - equal to 0.5,
-max equal to 0.8, -min equal to 0.2, and * equal to 0.3.
First, we put the animats with some internal needs in a scarce environment, as seen in
Figure 52. After more than ten thousand time cycles, half of the - values for imitation were in
the neighbourhood of -max, and half in the neighbourhood of -min. This was because, in a
scarce environment, animats tend to have similar internal needs, and thus imitation of
behaviours can be performed, and - would be increased. We also made an experiment with the
same initial state, only that one animat had a value of * equal to 1.0. This did not make much
difference in the adjustment of the -’s, because other animats did not have a higher percentage
of high values of - for the animat with a high * than for others at the end of the experiment.
The " values related with the internal needs that could not be satisfied were increased,
increasing the motivation degree.
Next, we put the animats with no internal needs in an abundant environment, as shown
in Figure 53. After more than ten thousand simulation cycles, all -’s were below their initial
value, and most in the neighbourhood of -min. This is because, in an abundant environment,
animats are wandering most of the time (remember that the adjustment of -’s only takes place
when the individual has internal motivations), and when one has internal needs enough to
trigger an appetitive or consummatory behaviour, in most of the cases the animats he is
perceiving are performing different actions, making all - ’s to tend to -min. For this case we
also made an experiment putting an animat with a value of * equal to 1.0, but again this did not
made a noticeable difference in the - values. Because of the abundant environment, the "
values related to the internal needs related to the abundant stimuli decreased, decreasing the
motivation degree.
A high value of * does not make a big difference because the behaviours produced by
BeCA were strongly motivated. For reactive behaviours, a high value of * makes a more
noticeable difference.
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