Person Response Functions and the Definition of Units in the Social Sciences

摘要

Humphry (this issue) has written a thought-provoking piece on the interpretation of item discrimination parameters as scale units in item response theory. One of the key features of his work is the description of an item response theory (IRT) model that he calls the logistic measurement function that combines aspects of two traditions in IRT that have their genesis in the measurement models of Rasch (1980) and Birnbaum (1968).