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…

Creativity tests, like creativity itself, vary widely in their structure and use. These differences include instructions, test duration, environments, prompt and response modalities, and the structure of test items. A key factor is task structure, referring to the specificity of the number of responses requested for a given prompt. Classic…

The Next Generation Science Standards propose a multidimensional model of science learning, comprised of Core Disciplinary Ideas, Science and Engineering Practices, and Crosscutting Concepts (NGSS Lead States, 2013). Accordingly, there is a need for student assessment aligned with the new standards. Creating assessments that validly and reliably…

In preparation for online administration of the ACT® test, ACT conducted studies to examine the comparability of scores between online and paper administrations, including a timing study in fall 2013, a mode comparability study in spring 2014, and a second mode comparability study in spring 2015. This report presents major findings from these…

This study compared three common vocabulary test formats, the Yes/No test, the Vocabulary Knowledge Scale (VKS), and the Vocabulary Levels Test (VLT), as measures of vocabulary difficulty. Vocabulary difficulty was defined as the item difficulty estimated through Item Response Theory (IRT) analysis. Three tests were given to 165 Japanese students,…

The Force Concept Inventory (FCI) is a 30-question multiple-choice assessment that has been a building block for much of the physics education research done today. In practice, there are often concerns regarding the length of the test and possible test-retest effects. Since many studies in the literature use the mean score of the FCI as the…

Modeling multidimensional test data with a unidimensional model can result in serious statistical errors, such as bias in item parameter estimates. Many methods exist for assessing the dimensionality of a test. The current study focused on DIMTEST. Using simulated data, the effects of sample size splitting for use with the ATFIND procedure for…

Teachers' professional knowledge is assumed to be a key variable for effective teaching. As teacher education has the goal to enhance professional knowledge of current and future teachers, this knowledge should be described and assessed. Nevertheless, only a limited number of studies quantitatively measures physics teachers' professional…

The equity properties can be used to assess the quality of an equating. The degree to which expected scores conditional on ability are similar between test forms is referred to as first-order equity. Second-order equity is the degree to which conditional standard errors of measurement are similar between test forms after equating. The purpose of…

Mixed-format assessments are increasingly being used in large scale standardized assessments to measure a continuum of skills ranging from basic recall to higher order thinking skills. These assessments are usually comprised of a combination of (a) multiple-choice items which can be efficiently scored, have stable psychometric properties, and…

This study tracked gender differential item functioning (DIF) on the English subtest of the Korean College Scholastic Aptitude Test (KCSAT) over a nine-year period across three data points, using both the Mantel-Haenszel (MH) and item response theory likelihood ratio (IRT-LR) procedures. Further, the study identified two factors (i.e. reading…

The traditional way of equating the scores on a new test form X to those on an old form Y is equipercentile equating for a population of examinees. Because the population is likely to change between the two administrations, a popular approach is to equate for a "synthetic population." The authors of the articles in this issue of the…

Four item response theory linking methods (2 moment methods and 2 characteristic curve methods) were compared to concurrent (CO) calibration with the focus on the degree of robustness to format effects (FEs) when applying the methods to multidimensional data that reflected the FEs associated with mixed-format tests. Based on the quantification of…

Discusses a procedure for testing the equivalence among different item response formats used in personality and attitude measurement. The procedure is based on the assumption that latent response variables underlie the observed item responses. It uses a nested series of confirmatory factor analysis models based on K. Joreskog's (1971) method for…

The first purpose of this study was to investigate the stability of two essential dimensionality measures across 10 random samples within a particular assessment item (AT1) selection. Other purposes were to investigate the discrepancy of the essential unidimensionality estimates for a test across different AT1 selections and sample sizes and to…