In recent ACT mode comparability studies, students testing on laptop or desktop computers earned slightly higher scores on average than students who tested on paper, especially on the ACT® reading and English tests (Li et al., 2017). Equating procedures adjust for such "mode effects" to make ACT scores comparable regardless of testing…

Students must choose when to take the ACT for the first time and if and when to retest. States and districts that administer the ACT test to all students must also choose when to administer the test. A key consideration in making these decisions is the impact on scores. Because the ACT is a curriculum-based test of academic achievement, students…

This manual contains technical information about the ACT® college readiness assessment. The principal purpose of this manual is to document the technical characteristics of the ACT in light of its intended purposes. ACT regularly conducts research as part of the ongoing formative evaluation of its programs. The research is intended to ensure that…

Views on testing--its purpose and uses and how its data are analyzed--are related to one's perspective on test takers. Test takers can be viewed as learners, examinees, or contestants. I briefly discuss the perspective of test takers as learners. I maintain that much of psychometrics views test takers as examinees. I discuss test takers as a…

In this study, we investigated whether preequating results agree with equating results that are based on observed operational data (postequating) for a college placement program. Specifically, we examined the degree to which item response theory (IRT) true score preequating results agreed with those from IRT true score postequating and from…

Various applications of item response theory often require linking to achieve a common scale for item parameter estimates obtained from different groups. This article used a simulation to examine the relative performance of four different item response theory (IRT) linking procedures in a random groups equating design: concurrent calibration with…

An analytic procedure for smoothing in equipercentile equating using cubic smoothing splines is described and illustrated. The effectiveness of the procedure is judged by comparing the results from smoothed equipercentile equating with those from other equating methods using multiple cross-validations for a variety of sample sizes. (Author/JKS)

The primary objective of this study was to find the smallest sample size for which equating based on a random groups design could be expected to result in less overall equating error than had no equating been conducted. Mean, linear, and equipercentile equating methods were considered. Some of the analyses presented in this paper assumed that the…

The effects of anchor test characteristics in the accuracy and precision of test equating in the "common items, nonequivalent groups design" were studied. The study also considered the effects of nonparallel based and new forms on the equating solution, and it investigated the effects of differential weighting on the success of equating…

For several years counselors have been interested in equating the ACT composite score with the SAT total score. This paper explores the possibility of using the first semester college grade point average as an anchor variable for equating the two tests. Research indicated that colleges should develop local conversion tables. (Author)

This paper focuses on methodological issues in applying equipercentile equating methods to pairs of tests that do not meet the assumptions of equating. This situation is referred to as a concordance situation, as opposed to an equating situation, and the end result is a concordance table that gives "comparable" scores between the tests.…

Distinctions were made between three classes of statistical linkage: equivalence, concordance, and prediction. These distinctions were based on rational content considerations and empirical statistical relationships. A large database involving SAT I and ACT scores was used to determine which type of linkage was best suited for different scores and…

This paper describes how results on the ACT and SAT I can be compared through statistical linking procedures.

In this paper a quadratic curve equating method for different test forms under a random-group data-collection design is proposed. Procedures for implementing this method and related issues are described and discussed. The quadratic-curve method was evaluated with real test data (from two 30-item subtests for a professional licensure examination…

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…