1. A method of classifying an input pattern into an associated class, comprising: extracting data pertaining to preselected features present within the input pattern; determining, via a first classification technique, a discriminant value for each of a plurality of classes reflecting the relative likelihood that a class is the associated class; selecting a class with the highest relative likelihood; generating, via a second classification technique, a confidence value reflective of the a posteriori probability that the selected class is the associated class; and rejecting the selected class if the determined confidence value is below a predetermined threshold value.