The purpose of this paper is to explore methods to approximate population invariance without conducting multiple linkings for subpopulations. Under the single group or equivalent groups design, no linking needs to be performed for the parallel-linear system linking functions. The unequated raw score information can be used as an approximation. For…

A procedure for checking the score equivalence of nearly identical editions of a test is described and illustrated with Scholastic Aptitude Test data. The procedure uses the standard error of equating and uses graphical representation of score conversion deviations from the identity function in standard error units. (SLD)

Combinations of five methods of equating test forms and two methods of selecting samples of students for equating were compared for accuracy. The two sampling methods were representative sampling from the population and matching samples on the anchor test score. The equating methods were: (1) the Tucker method; (2) the Levine method; (3) the…

An attempt was made to evaluate the standard error of equating (at the mean of the scores) in an ongoing testing program. The interest in estimating the empirical standard error of equating is occasioned by some discomfort with the error normally reported for test scores. Data used for this evaluation came from the Admissions Testing Program of…

This report builds on and extends existent research on population invariance to new tests and issues. The authors lay the foundation for a deeper understanding of the use of population invariance measures in a wide variety of practical contexts. The invariance of linear, equipercentile and IRT equating methods are examined using data from five…

The SAT® I: Reasoning Test is administered seven times a year. Primarily for security purposes, several different test forms are given at each administration. How is it possible to compare scores obtained from different test forms and from different test administrations? The purpose of this paper is to provide an overview of the statistical…

This paper describes the various ways in which the SAT has evolved since its introduction in 1926. Some of the modifications have involved changes in the types of questions used to measure verbal and mathematical skills. Other modifications focused on liberalizing time limits to ensure that speed of responding to questions has minimal effect on…