This paper presents a study of two learning criteria and two approaches to
using them for training neural network classifiers, specifically a Multi-La
yer Perceptron (MLP) and Radial Basis Function (RBF) networks. The first ap
proach, which is a traditional one, relies on the use of two popular learni
ng criteria i.e. learning via minimising a Mean Squared Error (MSE) functio
n or a Cross Entropy (CE) function. It is shown that the two criteria have
different charcteristics in learning speed and outlier effects, and that th
is approach does not necessarily result in a minimal classification error.
To be suitable for classification tasks, in our second approach an empirica
l classification criterion is introduced for the testing process while usin
g the MSE or CE function for the training. Experimental results on several
benchmarks indicate that the second approach, compared with the first, lead
s to an improved generalisation performance, and that the use of the CE fun
ction, compared with the MSE function, gives a faster training speed and im
proved or equal generalisation performance.