Exemplar models and decision bound models make remarkably similar predictions across a wide array of experimental settings. Although the models have been compared in terms of their overall quantitative fit to data, there is little evidence for a qualitative comparison. This article demonstrates that when probabilistic feedback is given to participants, the decision bound model predicts that this probabilistic feedback will not effects the participants response times. However, a random-walk exemplar model predicts that the probabilistic feedback will produce slowed response times. The results of the study confirmed the predictions of the random-walk exemplar model.