layer terminology

[guy smith]

		re: what does   N-layer   really mean?

  I agree with Scott Fahlman that the lack of an accepted meaning for N-layer
is confusing.

  In the context of nets as clearly layered as Back Propagation nets, I think
'N' should refer to the number of layers of weights, which is also the number
of layers of non-input nodes.

  Thus, a 0-layer net makes no sense, a single node is a 1-layer net, and 
the minimal net that can solve the XOR problem (calculating the parity of two 
binary inputs) is a 2-layer net.

  There is at least one rationale for this choice. If an N-layer net uses the
outputs of an M-layer net for its input, you end up with an N+M layer net.

Yours Pedantically,
Guy Smith.