Item analysis is an integral part of operational test development and is typically conducted within two popular statistical frameworks: classical test theory (CTT) and item response theory (IRT). In this digital ITEMS module, Hanwook Yoo and Ronald K. Hambleton provide an accessible overview of operational item analysis approaches within these…

The Angoff standard setting method relies on content experts to review exam items and make judgments about the performance of the minimally proficient examinee. Unfortunately, at times content experts may have gaps in their understanding of specific exam content. These gaps are particularly likely to occur when the content domain is broad and/or…

This article discusses the ResidPlots-2, a computer software that provides a powerful tool for IRT graphical residual analyses. ResidPlots-2 consists of two components: a component for computing residual statistics and another component for communicating with users and for plotting the residual graphs. The features of the ResidPlots-2 software are…

Differential item functioning (DIF) analyses are a routine part of the development of large-scale assessments. Less common are studies to understand the potential sources of DIF. The goals of this study were (a) to identify gender DIF in a large-scale science assessment and (b) to look for trends in the DIF and non-DIF items due to content,…

Essential for an effective criterion-referenced testing program is a set of test items that are "valid" indicators of the objectives they have been designed to measure. Unfortunately, the complex matter of assessing item validity has received only limited attention from educational measurement specialists. One promising approach to the item…

Georg Rasch has developed a new one-parameter latent trait model to explain the performance of examinees on achievement tests. The model can be viewed as a special case of Birnbaum's two-parameter logistic model where all items are assumed to have equal discriminating power. Birnbaum's model permits items to vary in discriminating power. Both…

The purpose of this paper is to describe some of the current changes in test development that are taking place because of the availability and capabilities of computers, especially microcomputers. Item banking and test assembly are discussed, and a comprehensive testing system is described. (BW)

The agreement between item response theory-based and Mantel Haenszel (MH) methods in identifying biased items on tests was studied. Data came from item responses of four spaced samples of 1,000 examinees each--two samples of 1,000 Anglo-American and two samples of 1,000 Native American students taking the New Mexico High School Proficiency…

The purpose of this research study was to assess item response model-test data fit using residuals. First, a comparison of raw and standardized residuals for describing model-test data fit was carried out. Second, hypotheses concerning the relationship between residual sizes and several item characteristics were studied. The analyses with…

Four methods for determining the dimensionality of a set of test items were compared: (1) linear factor analysis; (2) residual analysis; (3) nonlinear factor analysis; and (4) Bejar's method. Five artificial test data sets (for 40 items and 1500 examinees) were generated, consistent with the three-parameter logistic model and the assumption of…

Although item bias statistics are widely recommended for use in test development and test analysis work, problems arise in their interpretation. The purpose of the present research was to evaluate the validity of logistic test models and computer simulation methods for providing a frame of reference for item bias statistic interpretations.…

The purpose of the present research was to study, systematically, the "goodness-of-fit" of the one-, two-, and three-parameter logistic models. We studied, using computer-simulated test data, the effects of four variables: variation in item discrimination parameters, the average value of the pseudo-chance level parameters, test length,…

Comments are made on the review papers presented by six Dutch psychometricians: Ivo Molenaar, Wim van der Linden, Ed Roskam, Arnold Van den Wollenberg, Gideon Mellenbergh, and Dato de Gruijter. Molenaar has embraced a pragmatic viewpoint on Bayesian methods, using both empirical and pure approaches to solve educational research problems. Molenaar…

Latent trait models may offer considerable potential for the improvement of educational measurement practices, but until recently, they have received only limited attention from measurement specialists. This paper provides a brief introduction to latent trait models, and provides test practitioners with a non-technical introduction to the…

The study compared two promising item response theory (IRT) item-selection methods, optimal and content-optimal, with two non-IRT item selection methods, random and classical, for use in fixed-length certification exams. The four methods were used to construct 20-item exams from a pool of approximately 250 items taken from a 1985 certification…