A latent trait model, the Rasch, was fitted to a criterion-referenced test. Approximately 90 percent of the items fit the model. Those items which fit the model were then calibrated. Based on the item calibration, individual ability estimates and the standard errors of those estimates were calculated. Using the ability estimates, it was possible, given any criterion level, to compute the probability of a person exceeding the criterion. The calibration was done on the final examination of a performance-based introductory educational psychology course. (Author)