The assumptions of the Rasch model are discussed and the Rasch model is reformulated as a quasi-independence model. Using ordinary contingency table methods, the Rasch model can be tested generally or against less restrictive quasi-loglinear models to investigate specific violations of its assumptions. (Author/BW)

Graphing and statistics software permitting users to fit polynomial curves to scatter plots of data may display the equation generating the curve with numerical coefficients that have been rounded off to a few decimal places. The round-off error can produce anomalous findings due to systematic and extreme distortions of the fitted curve.…

A method based on the likelihood ratio procedure is presented for use in selecting a measurement model from among the Rasch, two-parameter, and three-parameter logistic latent trait models. (Author/BW)

Discusses the Linear Logistic Test Model (LLTM) and demonstrates that there are many equivalent ways to specify a model. Analyzed a real data set (300 responses to 5 analogies) using a Lagrange multiplier test for the specification of the model, and demonstrated that there may be many ways to change the specification of an LLTM and achieve the…

Issues arising from difference scores with zero reliability that nevertheless allow a powerful test of change are discussed. Issues include the appropriateness of underlying statistical models for psychological data and the relationship between difference scores and power. Increases in reliability always increase power for a fixed effect size.…

Discusses bibliometric studies of research collaboration and describes the development of a theoretical model for the distribution of authorship. The shifted Waring distribution model and 15 other probability models are tested for goodness-of-fit, and results are reported that indicate the shifted inverse Gaussian-Poisson model provides the best…

A nonspatial operationalization of the Krumhansl distance-density model of similarity is presented. The conceptual model and empirical evidence are reviewed. A nonspatial, tree-fitting methodology is described, which is sufficiently flexible to fit several competing hypotheses of similarity formation. Extensions to spatial models, three-way…

Using Goodman's (1975) notion of quasi-independence as a method of obtaining goodness of fit measures for non-scalable types in a scalogram analysis, archival data sets were examined using available Guttman scaling techniques, recent developments in latent structure analysis, and multidimensional scaling procedures. The Stouffer-Toby (1951) data…

The results of data analysis based on the multiplicative binomial model (MLTBIN) are compared with dichotomous data analyzed by using the simple logistic model (SLM). Specifically, the paper focuses on the issues of fit to these Rasch Models and estimates of item difficulty. The data indicate that the SLM and MLTBIN are not comparable in the…

Log linear models are proposed for the analysis of structural relations among multidimensional developmental contingency tables. Model of quasi-independence are suggested for testing specific hypothesized patterns of development. Transitions in developmental categorizations are described by Markov models applied to successive contingency tables. A…

A special case of Bloxom's version of Tucker's three mode factor analysis model is developed statistically. A goodness of fit test and an empirical example are presented. (Author/JKS)

The purpose of this study was to demonstrate a potential difficulty with relying on null models in LISREL confirmatory factor analytic measurement models and to offer several suggestions for dealing with this concern. Using randomly generated factors in a matrix of 46 aptitude tests, it was shown that this approach is unlikely to reject even…

A common functional relationship among Lotka's law, Bradford's law, and Zipf's law is derived. The proof takes explicit account of the sequences of observed values of the variables by means of an index. This approach results in a more realistic and precise formulation of each law. (Author/EM)