The New Training Alg for Feedforward Networks

[Luis B. Almeida]

Dr. Subhash C. Kak writes, in his message:

  The computing power of this algorithm may be gauged
  from the example that the exclusive-Or problem that requires several
  thousand iterative steps using the backpropagation algorithm was
  solved in 8 steps.

I cannot agree with the assertions made about the speed of
backpropagation in the XOR problem. Just to be sure, I have just run a
few tests, using plain backpropagation, in the batch mode, without any
acceleration technique (not even momentum), and using an architecture
with 2 input units, 2 hidden units and 1 output unit (more details
available on request). The runs that didn't stop at local minima, all
converged between 12 and 30 epochs. About 1/3 of the runs fell in
local minima.

Of course, this comment is not intended at denying the qualities of
the algorithm proposed by Dr. Kak, it is just intended at putting
backpropagation in its actual stand.

Luis B. Almeida

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