⁵Both Ashby (see Ashby & Waldron, 1999) and Nosofsky (1986, 1991) have obtained data similar to ours in which human participants categorized stimuli that were probabilistically associated with two response categories. Ashby’s approach is similar to our statistical decision model, Nosofsky’s is similar to our exemplar model. Perhaps because of the complexities associated with the analysis of performance by human participants, these investigators do not appear to be aware that both models are compatible, at least to a first approximation.