Rasch models are characterised by sufficient statistics for all parameters. In the Rasch unidimensional model for two ordered categories, the parameterisation of the person and item is symmetrical and it is readily established that the total scores of a person and item are sufficient statistics for their respective parameters. In contrast, in the…

Both the attenuation paradox of traditional test theory and the assumption of local independence in person-item response theory have caused problems in interpretation. This paper demonstrates that the two are related concepts, and, through this demonstration, both are clarified. It is demonstrated that the breakdown of local independence leads to…

This book discusses adapting pencil-and-paper tests to computerized testing. Mention is made of models for graded responses to items and of possibilities beyond pencil-and-paper-tests, but the book is essentially about dichotomously scored test items. Contrasts between item response theory and classical test theory are described. (SLD)

Reflects on the development of the unidimensional Rasch model for ordered categories and the resistance to some of its initially counterintuitive implications, especially that the thresholds that partition the continuum to form the ordered categories can show an empirical problem with the data. (SLD)

The cross-national WHO-study Health Behaviour in School-Aged Children (HBSC) is a comprehensive adolescent survey ongoing in Europe based on a public health perspective. The present study, examining the HBSC-instrument on subjective health, uses the unidimensional Rasch model. Items are analysed with respect to their operating characteristics…

A Rasch model for ordered response categories is derived and it is shown that it retains the key features of both the Thurstone and Likert approaches to studying attitude. Key features of the latter approaches are reviewed. Characteristics in common with the Thurstone approach are: statements are scaled with respect to their affective values;…

Developed a method for conditional pairwise estimation in the Rasch model for ordered response categories using principal components analysis and evaluated the procedure through a simulation study. Results show that the quality of the estimates is excellent. (SLD)

Uses a framework previously developed to relate outcomes based education and B. Bloom's "Taxonomy of Educational Objectives" to consider ways in which modern test theory can be used to connect aspects of assessment to the curriculum framework and to consider insights this connection might provide. (SLD)

Two classes of graded response models, one based on the work of L. L. Thurstone and the other on the work of G. Rasch, are juxtaposed and shown to satisfy important but mutually incompatible criteria and to reflect different response processes. Implications of the choice between these models are discussed. (Author/SLD)

The hyperbolic cosine unfolding model for direct responses (HCMDR) of persons to individual stimuli is elaborated in three ways. The specialization of the second parameter is shown to be a property of the data, and not arbitrary. The HCMDR is used to construct an elegant model for pairwise preferences. (SLD)

When the logistic function is substituted for the normal, Thurstone's Case V specialization of the law of comparative judgment for paired comparison responses gives an identical equation for the estimation of item scale values, as does the Rasch formulation for direct responses. Comparisons are made. (Author/CTM)

An elaboration of a psychometric model for rated data, which belongs to the class of Rasch models, is shown to provide a model with two parameters, one characterizing location and one characterizing dispersion. Characteristics of the dispersion parameter are discussed. (Author/JKS)

The distinction between deterministic and statistical reasoning in the application of models to educational measurement is explicated. Issues addressed include the relationship between data and estimation equations, distinction between parameters and parameter estimates, and power of tests of fit of responses across the ability continuum. (TJH)

The conceptualization of teacher role has led to the six-factor Role Dimension Profile Scale. When responses to the scale used with a Likert data collection format are analyzed, the resulting single dimension is interpreted as the teacher's "professional horizon." Implications of these results are discussed. (Author/GSK)

A simple probabilistic model for unfolding data collected by a direct response design in which responses were scored dichotomously was applied to the measurement of attitudes toward capital punishment. Responses conformed to the unfolding mechanism. Scale values of the statements were statistically equivalent to those of Thurstone's methods. (SLD)