The nonequivalent groups anchor test (NEAT) design is often used to scale item parameters from two different test forms. A subset of items, called the anchor items or common items, are administered as part of both test forms. These items are used to adjust the item calibrations for any differences in the ability distributions of the groups taking…

In the framework of the observed-score equating methods for the nonequivalent groups with anchor test design, there are 3 fundamentally different ways of using the information provided by the anchor scores to equate the scores of a new form to those of an old form. One method uses the anchor scores as a conditioning variable, such as the Tucker…

The impact of particular types of context effects on actual scores is less understood although there has been some research carried out regarding certain types of context effects under the nonequivalent anchor test (NEAT) design. In addition, the issue of the impact of item context effects on scores has not been investigated extensively when item…

This booklet grew out of a half-day class on equating that author Samuel Livingston teaches for new statistical staff at Educational Testing Service (ETS). The class is a nonmathematical introduction to the topic, emphasizing conceptual understanding and practical applications. The class consists of illustrated lectures, interspersed with…

Population invariance in equating exists when the relationship between two scales is the same for two or more subpopulations of examinees and hence the function used to equate the scales is not dependent on subpopulations. A lack of equating invariance (i.e., equating dependence) leads to a situation whereby examinees having the same score on one…

This study investigates a sequence of item response theory (IRT) true score equatings based on various scale transformation approaches and evaluates equating accuracy and consistency over time. The results show that the biases and sample variances for the IRT true score equating (both direct and indirect) are quite small (except for the mean/sigma…

We demonstrate how to assess the potential changes to a test's score scale necessitated by changes to the test specifications when a field study is not feasible. We used a licensure test, which is currently under revision, as an example. We created two research forms from an actual form of the test. One research form was developed with the current…

The desirability of test equating to maintain the same criterion standard from test administration to test administration has long been accepted for multiple choice tests. The same consistency of expectations is desirable for performance tests, especially if they are part of a licensure or certification process or used for other high stakes…

Recently, there has been an increasing level of interest in subscores for their potential diagnostic value. Haberman (2008b) suggested reporting an augmented subscore that is a linear combination of a subscore and the total score. Sinharay and Haberman (2008) and Sinharay (2010) showed that augmented subscores often lead to more accurate…

Given that equating/linking applications are now appearing in kinesiology literature, this article provides an overview of the different types of linked test scores: equated, concordant, and predicted. It also addresses the different types of evidence required to determine whether the scores from two different field tests (measuring the same…

The standard error of equating quantifies the variability in the estimation of an equating function. Because common items for deriving equated scores are treated as fixed, the only source of variability typically considered arises from the estimation of common-item parameters from responses of samples of examinees. Use of alternative, equally…

For those tests solely composed of testlets, local item independency assumption tends to be violated. This study, by using empirical data from a large-scale state assessment program, was interested in investigates the effects of using different models on equating results under the non-equivalent group anchor-test (NEAT) design. Specifically, the…

In the nonequivalent groups with anchor test (NEAT) design, the standard error of linear observed-score equating is commonly estimated by an estimator derived assuming multivariate normality. However, real data are seldom normally distributed, causing this normal estimator to be inconsistent. A general estimator, which does not rely on the…

The "single group with nearly equivalent tests" (SiGNET) design proposed here was developed to address the problem of equating scores on multiple-choice test forms with very small single-administration samples. In this design, the majority of items in each new test form consist of items from the previous form, and the new items that were…

Recently, the literature has seen increasing interest in subscores for their potential diagnostic values; for example, one study suggested the report of weighted averages of a subscore and the total score, whereas others showed, for various operational and simulated data sets, that weighted averages, as compared to subscores, lead to more accurate…