Consider N pairs of I-dimensional "I" nput vectors and O-dimensional "O"utput target vectors. If Ntrn is the number of training pairs, the number of training equations is
Ntrneq = Ntrn*O
If SSEtrn is the sum of squared training subset errors, corresponding mean-square-error, MSEtrn is given by
MSEtrn = SSEtrn/Ntrneq
For an I-H-O feedforward net, the number of unknown weight variables to be estimated by the training subset pairs is
Nw = (I+1)*H+(H+1)*O = O + (I+O+1)*H
resulting in the number of training degrees-of-freedom
Ntrndof = Ntrneq - Nw
Therefore, the DOF adjusted training set mean-square-error is given by
MSEtrna = SSEtrn/ Ntrndof
I have posted zillions of examples in both the NEWSGROUP and ANSWERS. Some examples can be obtained with the search words
greg MSEa
or
greg MSEtrna
Hope this helps.
Thank you for formally accepting my answer
Greg
