The data set contains both response patterns and item parameters estimates following a 3PL model
for two 36-items tests forms. Form X
was administered to 1655 examinees and form Y
to 1638 examinees. Also, 12 out of the 36 items are common between both test forms (items 3, 6, 9,
12, 15, 18, 21, 24, 27, 30, 33, 36). This data has been described and analized by Kolen and Brennan (2004).