Thank you for all the previous support. I have another question: I am using eRm to run a partial credit model. Is there a way to ask eRm to compute and present to me the probability of a person with a specific ability to achieve each one of the scores 0, 1, 2, 3, or 4 on a specific question with known step measures (thresholds)? I checked the documentation but there is no relevant info. (actually, it says that only in the case of the simple Rasch model has the prediction function been written - but again, how are the residuals computed if such a function does not exist?) Thank you for your time Dr. Iasonas Lamprianou Department of Social and Political Sciences University of Cyprus [[alternative HTML version deleted]]