The purpose of this research is to examine the comparability of mathematics and science scores for students from English language backgrounds (ELB) and non-English language backgrounds (NELB). We examine the relationship between English reading proficiency and performance on mathematics and science assessments in Australia, Canada, the United…

Raju, van der Linden, and Fleer (1995) introduced a framework for differential functioning of items and tests (DFIT) for unidimensional dichotomous models. Since then, DFIT has been shown to be a quite versatile framework as it can handle polytomous as well as multidimensional models both at the item and test levels. However, DFIT is still limited…

In this study, we contrast results from two differential item functioning (DIF) approaches (manifest and latent class) by the number of items and sources of items identified as DIF using data from an international reading assessment. The latter approach yielded three latent classes, presenting evidence of heterogeneity in examinee response…

The purpose of this study was to explore what may be contributing to differences in performance in mathematics on the Trends in International Mathematics and Science Study 2007. This was done by using a mixture item response theory modeling approach to first detect latent classes in the data and then to examine differences in performance on items…

In this article, we investigate the creation of comparable score scales across countries in international assessments. We examine potential improvements to current score scale calibration procedures used in international large-scale assessments. Our approach seeks to improve fairness in scoring international large-scale assessments, which often…

The International Test Commission's "Guidelines for Translating and Adapting Tests" (2010) provide important guidance on developing and evaluating tests for use across languages. These guidelines are widely applauded, but the degree to which they are followed in practice is unknown. The objective of this study was to perform a…

Understanding adolescent self-concept is of great concern for educators, mental health professionals, and parents, as research consistently demonstrates that low self-concept is related to a number of problem behaviors and poor outcomes. Thus, accurate measurements of self-concept are key, and the validity of such measurements, including the…

The aim of this study was to examine log linear modelling (LLM) compared with logistic regression (LR) and Mantel-Haenszel (MH) test for detecting Differential Item Functioning (DIF) in a mastery test. The three methods were chosen because they have similar components. The results showed fairly high matching percentages together with high…

We present an extension of the logistic regression procedure to identify dichotomous differential item functioning (DIF) in the presence of more than two groups of respondents. Starting from the usual framework of a single focal group, we propose a general approach to estimate the item response functions in each group and to test for the presence…

In this study, the Canadian English and French versions of the Problem-Solving Measure of the Programme for International Student Assessment 2003 were examined to investigate their degree of measurement comparability at the item- and test-levels. Three methods of differential item functioning (DIF) were compared: parametric and nonparametric item…

International large-scale assessments of achievement often have a large degree of differential item functioning (DIF) between countries, which can threaten score equivalence and reduce the validity of inferences based on comparisons of group performances. It is important to understand potential sources of DIF to improve the validity of future…

Differential item functioning (DIF) analysis is a statistical technique used for ensuring the equity and fairness of educational assessments. This study formulates a new DIF analysis method using the information similarity index (ISI). ISI compares item information functions when data fits the Rasch model. Through simulations and an international…

Comparisons of human characteristics across different language groups and cultures become more important in today's educational assessment practices as evidenced by the increasing interest in international comparative studies. Within this context, the fairness of the results across different language and cultural groups draws the attention of…

This study investigates the effect of reporting the unadjusted raw scores in a high-stakes language exam when raters differ significantly in severity and self-selected questions differ significantly in difficulty. More sophisticated models, introducing meaningful facets and parameters, are successively used to investigate the characteristics of…

There has been considerable research regarding the extent to which psychometric sound assessments sometimes yield individual score estimates that are inconsistent with the response patterns of the individual. It has been suggested that individual response patterns may differ from expectations for a number of reasons, including subject motivation,…