DIMPACK Version 1.0 for assessing test dimensionality based on a nonparametric conditional covariance approach is reviewed. This software was originally distributed by Assessment Systems Corporation and now can be freely accessed online. The software consists of Windows-based interfaces of three components: DIMTEST, DETECT, and CCPROX/HAC, which…

Assessing individual change is an important topic in both psychological and educational measurement. An adaptive measurement of change (AMC) method had previously been shown to exhibit greater efficiency in detecting change than conventional nonadaptive methods. However, little work had been done to compare different procedures within the AMC…

Conservative bias in rejection of a null hypothesis from using the continuity correction in the Mantel-Haenszel (MH) procedure was examined through simulation in a differential item functioning (DIF) investigation context in which statistical testing uses a prespecified level [alpha] for the decision on an item with respect to DIF. The standard MH…

This Monte Carlo study compares the ability of the parametric bootstrap version of DIMTEST with three goodness-of-fit tests calculated from a fitted NOHARM model to detect violations of the assumption of unidimensionality in testing data. The effectiveness of the procedures was evaluated for different numbers of items, numbers of examinees,…

DIMTEST is a nonparametric hypothesis-testing procedure designed to test the assumptions of a unidimensional and locally independent item response theory model. Several previous Monte Carlo studies have found that using linear factor analysis to select the assessment subtest for DIMTEST results in a moderate to severe loss of power when the exam…

A statistical test for detecting answer copying on multiple-choice tests based on Cohen's kappa is proposed. The test is free of any assumptions on the response processes of the examinees suspected of copying and having served as the source, except for the usual assumption that these processes are probabilistic. Because the asymptotic null and…

DETECT is a nonparametric "full" dimensionality assessment procedure that clusters dichotomously scored items into dimensions and provides a DETECT index of magnitude of multidimensionality. Four factors (test length, sample size, item response theory [IRT] model, and DETECT index) were manipulated in a Monte Carlo study of bias, standard error,…

The accuracy of the large sample standard error of weighted kappa appropriate to the non-null case was studied by computer simulation for the hypothesis that two independently derived estimates of weighted kappa are equal, and for setting confidence limits around a single value of weighted kappa. (Author/CTM)

This computer program computes the adjusted alpha level using the original Bonferroni procedure and four modified Bonferroni procedures. It is written in Statistical Analysis System (SAS) macro language. Input and output features are described. (SLD)

General normal ogive and logistic multiple-group models for paired comparisons data are described. In these models, scale value and discriminal dispersion parameters are allowed to vary across stimuli and respondent populations. Model fitting and hypothesis testing are illustrated using health care coverage data from two age groups. (SLD)

Semantic incompatibility, an error in constructing measuring instruments for rating oneself, others, or objects, refers to the extent to which item wordings are incongruent with, and hence inappropriate for, scale labels and vice versa. This study examines the effects of semantic incompatibility on rating responses. Using a 2 x 2 factorial design…

An approximate statistical test is derived for the hypothesis that the intraclass reliability coefficients associated with two measurement procedures are equal. Control of Type 1 error is investigated by comparing empirical sampling distributions of the test statistic with its derived theoretical distribution. A numerical illustration is…

Research on the direct-product model is extended by deriving hierarchically nested models for explicitly testing the patterns of method and trait factors and through formal tests developed for the pattern of communalities. These procedures are illustrated, and use of the MUTMUM computer program is discussed. (SLD)

This note shows that, under conditions specified by Levin and Subkoviak (TM 503 420), it is not necessary to specify the reliabilities of observed scores when comparing completely randomized designs with randomized block designs. Certain errors in their illustrative example are also discussed. (Author/CTM)

Comments (TM 503 706) on an earlier article (TM 503 420) concerning the comparison of the completely randomized design and the randomized block design are acknowledged and appreciated. In addition, potentially misleading notions arising from these comments are addressed and clarified. (See also TM 503 708). (Author/CTM)