I have a dataset of test results. There are 400 students, and 100 items. I ran ltm::rasch in R, and I computed ability scores for each student, and difficulty scores for each item.
I would now like to reuse this model. There is a method called fitted that allows you to compute a new student's ability, even if that student was not part of the original dataset.
How is fitted implemented? In other words, how can I use a pretrained Rasch model to compute ability scores for new students?
