In this digital ITEMS module, Dr. Stella Kim provides an overview of multidimensional item response theory (MIRT) equating. Traditional unidimensional item response theory (IRT) equating methods impose the sometimes untenable restriction on data that only a single ability is assessed. This module discusses potential sources of multidimensionality…

While significant attention has been given to test equating to ensure score comparability, limited research has explored equating methods for rater-mediated assessments, where human raters inherently introduce error. If not properly addressed, these errors can undermine score interchangeability and test validity. This study proposes an equating…

In this study, Kernel test equating methods were compared under NEAT and NEC designs. In NEAT design, Kernel post-stratification and chain equating methods taking into account optimal and large bandwidths were compared. In the NEC design, gender and/or computer/tablet use was considered as a covariate, and Kernel test equating methods were…

The purpose of the current article is to introduce the equating and evaluation methods used in this special issue. Although a comprehensive review of all existing models and methodologies would be impractical given the format, a brief introduction to some of the more popular models will be provided. A brief discussion of the conditions required…

Equating of psychometric scales and tests is frequently required and conducted in educational, behavioral, and clinical research. Construct comparability or equivalence between measuring instruments is a necessary condition for making decisions about linking and equating resulting scores. This article is concerned with a widely applicable method…

Maintaining equivalent performance standards across forms is a psychometric challenge exacerbated by small samples. In this study, the accuracy of two equating methods (Rasch anchored calibration and nominal weights mean) and four anchor item selection methods were investigated in the context of very small samples (N = 10). Overall, nominal…

Recent research has suggested that re-setting the standard for each administration of a small sample examination, in addition to the high cost, does not adequately maintain similar performance expectations year after year. Small-sample equating methods have shown promise with samples between 20 and 30. For groups that have fewer than 20 students,…

In test equating, one critical equating property is the group invariance property which indicates that the equating function used to convert performance on each alternate form to the reporting scale should be the same for various subgroups. To mitigate the impact of disrupted learning on the item parameters during the COVID-19 pandemic, a…

Lord's (1980) equity theorem claims observed-score equating to be possible only when two test forms are perfectly reliable or strictly parallel. An analysis of its proof reveals use of an incorrect statistical assumption. The assumption does not invalidate the theorem itself though, which can be shown to follow directly from the discrete nature of…

The purposes of this research are: 1) to compare two equalizing tests conducted with Hebara and Stocking Lord method; 2) to describe the characteristics of each equalizing test method using windows' IRTEQ program. This research employs a participatory approach as the data are collected through questionnaires based on the National Examination…

In this study we evaluated the stability of item parameters and student scores, using the pre-equated (pre-pandemic) parameters from Spring 2019 and post-equated (post-pandemic) parameters from Spring 2021 in two calibration and equating designs related to item parameter treatment: re-estimating all anchor parameters (Design 1) and holding the…

An important assumption of item response theory is item parameter invariance. Sometimes, however, item parameters are not invariant across different test administrations due to factors other than sampling error; this phenomenon is termed item parameter drift. Several methods have been developed to detect drifted items. However, most of the…

This study defines subpopulation item parameter drift (SIPD) as a change in item parameters over time that is dependent on subpopulations of examinees, and hypothesizes that the presence of SIPD in anchor items is associated with bias and/or lack of invariance in three psychometric outcomes. Results show that SIPD in anchor items is associated…

Three local observed-score kernel equating methods that integrate methods from the local equating and kernel equating frameworks are proposed. The new methods were compared with their earlier counterparts with respect to such measures as bias--as defined by Lord's criterion of equity--and percent relative error. The local kernel item response…

This paper presents a method for equating writing assessments using pairwise comparisons which does not depend upon conventional common-person or common-item equating designs. Pairwise comparisons have been successfully applied in the assessment of open-ended tasks in English and other areas such as visual art and philosophy. In this paper,…