While linear programming is a common tool in business and industry, there have not been many applications in educational assessment and only a handful of individuals have been actively involved in conducting psychometric research in this area. Perhaps this is due, at least in part, to the complexity of existing software packages. This article…

This paper proposes a general model for free-response data collected for measuring a specified unidimensional psychological process; systematizes situations which vary with respect to the scoring level of items; and finds out general conditions for the operating characteristic of an item response category to provide a unique maximum likelihood…

It is shown that empirical mental test P - P plots are approximately equal to theoretical item-item curves, at least for long tests administered to many people. This result is important because it leads to (1) a distribution free method for estimating points on item-item curves; (2) a general method for defining estimates of item parameters; and…