Errors in item parameter estimates have a negative impact on the accuracy of item and test information functions. The estimation errors may be random, but because items with higher levels of discriminating power are more likely to be selected for a test, and these items are most apt to contain positive errors, the result is that item information…

The development and evaluation of methods for detecting potentially biased items or differentially functioning items (DIF) represent a critical area of research for psychometricians because of the negative impact of biased items on test validity. A summary is provided of the authors' 12 years of research at the University of Massachusetts…

The potential of item response theory (IRT) for solving a number of testing problems in the Maryland Functional Reading Program would appear to be substantial in view of the many other promising applications of the theory. But, it is well-known that the advantages derived from an IRT model cannot be achieved when the fit between an item response…

Addressing the shortcomings of classical item statistics for selecting criterion-referenced test items, this paper describes an optimal item selection procedure utilizing item response theory (IRT) and offers examples in which random selection and optimal item selection methods are compared. Theoretical advantages of optimal selection based upon…

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 general goal of this paper is to help researchers conduct appropriately designed goodness of fit studies for item response model applications. The specific purposes are to describe: (1) an up-to-date set of promising and useful methods for addressing a variety of goodness of fit questions; and (2) current research studies to advance this set…

A brief overview of item response theory is provided, and a 186-item bibliography of books and articles on the subject dating from 1953 to June 1989 is presented. The overview includes a definition of the theory, a discussion of its development and application, and comparisons with classical test theory. All publications in the bibliography were…

Though item bias statistics are widely recommended for use in test development and analysis, problems arise in their interpretation. This research evaluates logistic test models and computer simulation methods for providing a frame of reference for interpreting item bias statistics. Specifically, the intent was to produce simulated sampling…

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…

Four item bias methods were studied. The methods compared include the Mantel-Haenszel statistic, the plot method, the route mean squared difference method, and the total area method; the latter two methods are based on item response theory. The test consisted of item responses of 451 male and 486 female ninth graders to 75 test items on the 1985…

Topics concerning latent trait theory are addressed: (1) dimensionality of latent space, local independence, and item characteristic curves; (2) models--equations, parameter estimation, testing assumptions, and goodness of fit, (3) applications test developments, item bias, tailored testing and equating; and (4) advantages over classical…

The validity of logistic test models and computer simulation methods for generating sampling distributions of item bias statistics was evaluated under the hypothesis of no item bias. Test data from 937 ninth-grade students were used to develop 7 steps for applying computer-simulated baseline statistics in test development. (SLD)