The present study investigates the influence of multidimensionality on linking and equating in a unidimensional IRT. Two hypothetical multidimensional scenarios are explored under a nonequivalent group common-item equating design. The first scenario examines test forms designed to measure multiple constructs, while the second scenario examines a…

This dissertation was designed to foster a deeper understanding of population invariance in the context of composite-score equating and provide practitioners with guidelines for addressing score equity concerns at the composite score level. The purpose of this dissertation was threefold. The first was to compare different composite equating…

The nonequivalent-groups anchor-test (NEAT) data-collection design is commonly used in large-scale assessments. Under this design, different test groups take different test forms. Each test form has its own unique items and all test forms share a set of common items. If item response theory (IRT) models are applied to analyze the test data, the…

This three-article dissertation aims to address three methodological challenges to ensure comparability in educational research, including scale linking, test equating, and propensity score (PS) weighting. The first study intends to improve test scale comparability by evaluating the effect of six missing data handling approaches, including…

Psychometricians at an organization named the Education and Training Evaluation Commission (ETEC) developed a new test scoring method called the latent D-scoring method (DSM-L) where it is believed that the new method itself is much easier and more efficient to use compared to the Item Response Theory (IRT) method. However, there are no studies…

For equating tests that measure several distinct proficiencies, procedures that reflect the multidimensional structure of the data are needed. Although there exist a few equating procedures developed under the multidimensional item response theory (MIRT) framework, there is a need for further research in this area. Therefore, the primary…

Preservation of equity properties was examined using four equating methods--IRT True Score, IRT Observed Score, Frequency Estimation, and Chained Equipercentile--in a mixed-format test under a common-item nonequivalent groups (CINEG) design. Equating of mixed-format tests under a CINEG design can be influenced by factors such as attributes of the…

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…

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…

Common test items play an important role in equating multiple test forms under the common-item nonequivalent groups design. Inconsistent item parameter estimates among common items can lead to large bias in equated scores for IRT true score equating. Current methods extensively focus on detection and elimination of outlying common items, which…

The kernel method of test equating is a unified approach to test equating with some advantages over traditional equating methods. Therefore, it is important to evaluate in a comprehensive way the usefulness and appropriateness of the Kernel equating (KE) method, as well as its advantages and disadvantages compared with several popular item…

The purpose of this research was to compare the equating performance of various equating procedures for the multidimensional tests. To examine the various equating procedures, simulated data sets were used that were generated based on a multidimensional item response theory (MIRT) framework. Various equating procedures were examined, including…

Mixed-format tests containing both multiple-choice (MC) items and constructed-response (CR) items are now widely used in many testing programs. Mixed-format tests often are considered to be superior to tests containing only MC items although the use of multiple item formats leads to measurement challenges in the context of equating conducted under…

The Non-Equivalent groups with Anchor Test equating (NEAT) design is a widely used equating design in large scale testing that involves two groups that do not have to be of equal ability. One group P gets form X and a group of items A and the other group Q gets form Y and the same group of items A. One of the most commonly used equating methods in…

Testing programs often use multiple test forms of the same test to control item exposure and to ensure test security. Although test forms are constructed to be as similar as possible, they often differ. Test equating techniques are those statistical methods used to adjust scores obtained on different test forms of the same test so that they are…