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Chapter 18
the Kohonen network, not presented in detail here, learn in ways that
exhibit a striking resemblance to creature learning.
Input Normalization
One of the most serious impediments to widespread use of the
Kohonen network is the fact that its inputs are subject to serious
restrictions. Ideally, they should he within symmetric boimds, usually
taken to be [-1, 1]. The length of the input vector must be the same
for all training and test cases. This length is typically chosen to be 1.
Finally, for best performance, each input should be able to cover the
majority of its range. For example, if some of the input variables are
physicall ...