This article describes the results of a simulation study to investigate the impact of missing data on the detection of differential item functioning (DIF). Specifically, it investigates how four methods for dealing with missing data (listwise deletion, zero imputation, two-way imputation, response function imputation) interact with two methods of…

Diagnostic assessment is currently an active research area in educational measurement. Literature related to diagnostic modeling has been in existence for several decades, but a great deal of research has been conducted within the last decade or so, especially within the last five years. The author summarizes the key components in the application…

This study examined variations of a nonequivalent groups equating design used with constructed-response (CR) tests to determine which design was most effective in producing equivalent scores across the two tests to be equated. Using data from a large-scale exam, the study investigated the use of anchor CR item rescoring in the context of classical…

In assessment, the ability to construct test items that measure a targeted skill is fundamental to validity and alignment. The ability to do the reverse is also important: determining what skill an existing test item measures. This paper presents a model for classifying test items that builds on procedures developed by others, including Bloom…

The influence of general and verbal ability on each of 72 verbal analogy test items were investigated with new factor analytical techniques. The analogy items together with the Computerized Swedish Enlistment Battery (CAT-SEB) were given randomly to two samples of 18-year-old male conscripts (n = 8566 and n = 5289). Thirty-two of the 72 items had…

Background: To establish credible, defensible and acceptable passing scores for written tests is a challenge for health profession educators. Angoff procedures are often used to establish pass/fail decisions for written and performance tests. In an Angoff procedure judges' expertise and professional skills are assumed to influence their ratings of…

In the course of screening a form of a medical licensing exam for items that function differentially (DIF) between men and women, the authors used the traditional Mantel-Haenszel (MH) statistic for initial screening and a Bayesian method for deeper analysis. For very easy items, the MH statistic unexpectedly often found DIF where there was none.…

The examination of measurement invariance in polytomous items is complicated by the possibility that the magnitude and sign of lack of invariance may vary across the steps underlying the set of polytomous response options, a concept referred to as differential step functioning (DSF). This article describes three classes of nonparametric DSF effect…

A new method for analyzing differential item functioning is proposed to investigate the relative strengths and weaknesses of multiple groups of examinees. Accordingly, the notion of a conditional measure of difference between two groups (Reference and Focal) is generalized to a conditional variance. The objective of this article is to present and…

We describe the results of an experiment conducted to test predictions about student responses to questions about motion based on an explicit model of student thinking in terms of the cuing of a variety of different physical intuitions or conceptual resources. This particular model allows us to account for observed variations in patterns of…

Methods are presented for comparing grades obtained in a situation where students can choose between different subjects. It must be expected that the comparison between the grades is complicated by the interaction between the students' pattern and level of proficiency on one hand, and the choice of the subjects on the other hand. Three methods…

When expectations and stereotypes are activated at retrieval, they spontaneously create distorted and illusory recollections that are consistent with these expectations. Participants studied doctor (physician)-related and lawyer-related statements that were presented by 2 different people. When informed, on a subsequent source memory test, (i.e.,…

Mixed-format tests containing both multiple-choice and constructed-response items are widely used on educational tests. Such tests combine the broad content coverage and efficient scoring of multiple-choice items with the assessment of higher-order thinking skills thought to be provided by constructed-response items. However, the combination of…

Federal legislation such as "No Child Left Behind" mandated that students with disabilities be included in accountability standards, creating an important responsibility to fairly assess all students, even those with disabilities. Consequently, a sense of urgency was placed on the entire educational system to ensure that these students…

This study examined the effect of linguistic modification on middle school students' ability to show what they know and can do on math assessments. REL West's study on middle school math assessment accommodations found that simplifying the language--or linguistic modification--on standardized math test items made it easier for English Language…