This study aims to analyze the differential bundle functioning in multidimensional tests with a specific purpose to detect this effect through differentiating the location of the item with DIF in the test, the correlation between the dimensions, the sample size, and the ratio of reference to focal group size. The first 10 items of the test that is…

Numerous researchers have suggested that there are multiple mathematical knowledge and skill areas needed by teachers in order for them to be effective teachers of mathematics: knowledge of the mathematics that are the goals of instruction, advanced mathematics beyond the instructional material, and mathematical knowledge that is specific to what…

When using IRT models in Educational Achievement Testing, the model is as a rule too simple to catch all the relevant dimensions in the test. It is argued that a simple model may nevertheless be useful but that it can be complemented with additional analyses. Such an analysis, called profile analysis, is proposed and applied to the reading data of…

The G index of agreement does not permit the use of various weights for its various items. The weighted G index described here, make it possible to use unequal weights. An example of the procedure is provided. (Author/JKS)

Generalizations of the G index as a measure of similarity between persons beyond the dichotomous situation are discussed. An attempt is made to present a generalization that does not require dichotomization of the items for cases where the number of response alternatives may differ. (Author/JKS)

The purpose of this paper is to present a generalization of the concept of item difficulty to test items that measure more than one dimension. Three common definitions of item difficulty were considered: the proportion of correct responses for a group of individuals; the probability of a correct response to an item for a specific person; and the…

The consequences of using item response theory (IRT) item bias detecting procedures with multidimensional IRT item data are examined. Limitations in procedures for detecting item bias are discussed. (SLD)

Cliff's Index "c" derived from an item dominance matrix is utilized in a clustering approach, termed extracting Reliable Guttman Orders (ERGO), to isolate Guttman-type item hierarchies. A comparison of factor analysis to the ERGO is made on social distance data involving multiple ethnic groups. (Author/BW)

The purpose of this paper is to further the cause of clarifying construct interpretations of tests, by proposing that non-metric multidimensional scaling may be more useful than factor analysis or other latent structure models for investigating the internal structure of tests. It also suggests that typical problems associated with scaling…

DETECT, the acronym for Dimensionality Evaluation To Enumerate Contributing Traits, is an innovative and relatively new nonparametric dimensionality assessment procedure used to identify mutually exclusive, dimensionally homogeneous clusters of items using a genetic algorithm ( Zhang & Stout, 1999). Because the clusters of items are mutually…

Little is known about environmental concerns and attitudes among people in former Soviet bloc countries in Eastern Europe despite widespread perceptions of severe environmental problems. The authors addressed this gap by examining Bulgarians' environmental concerns with a focus on whether the new environmental paradigm (NEP) scale can reliably…

Multidimensional item response theory (IRT) models have been proposed for better understanding the dimensional structure of data or to define diagnostic profiles of student learning. A compensatory multidimensional two-parameter partial credit model (M-2PPC) for constructed-response items is presented that is a generalization of those proposed to…

A few multi-dimensional items were found to be more efficient than a larger number of uni-dimensional items in tests for participant selection and evaluation of such compensatory educational programs as Title I. A multi-dimensional scaling technique is described which derives scores for each item on three dimensions, and allows multiple scores to…

The effects of varying degrees of correlation between abilities and of various correlation configurations between item parameters on ability and item parameter estimation using the three parameter logistic model were examined. Ten two-trait configurations and one unidimensional test configuration for 30 item tests were simulated. Each…

Many researchers have suggested that the cause of differential item functioning (DIF) can in part be due to the misspecification of the supporting trait distribution (STD). This paper demonstrates how a unidimensional item response theory (IRT) calibration of response data, generated from a two-dimensional IRT model, results in DIF when the…