A tailored testing model employing the beta distribution, whose mean equals the difficulty of an item and whose variance is approximately equal to the sampling variance of the item difficulty, and employing conditional item difficulties, is proposed. The model provides a procedure by which a minimum number of items of a test, consisting of a set…

A linear regression model was used to select items from a pool of 700 arithmetic word problems to be used in a computer-assisted mathematics curriculum for elementary school students. The experimental procedure first involved a stepwise linear regression analysis of a student's performance over a set of 25 problems. The probability correct for…