I was doing research to charatrize group of people into four levels ability. I use a partial credit model to analyze data. How to know the probability of each person in category level with ministep software.
Amin, sorry, Winsteps does not report the probability of each category of each item for each person directly. Winsteps does report the probability of each category of each item relative to the item difficulty. So, please (1) compute the relative measure = (person ability - item difficulty) (2) then look up the relative measure in the GRFILE= to obtain the probability of each category for the person on the item.