"Layers"

[Terry Sejnowski <terry@cs.jhu.edu>]

Lets not lock ourselves into a terminology that applies
to only a special case -- feedforward nets.  When feedback
connections are allowed the relationships between the
units become more complex.  For example, in Pineda's
recurrent backprop algorithm, the distinction between
input and output units is blurred -- the same unit can
have both roles.  The only distinction that remains is
that of hidden units, and the number of synapses
separating a given hidden units from a given input or
output unit.  The topologies can get quite complex.

Terry

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