Grading on the curve is a common practice in higher education. While there are many critics of the practice it still finds wide spread acceptance particularly in science classes. Advocates believe that in large classes student ability is likely to be normally distributed. If test scores are also normally distributed instructors and students tend…

This article examines how conversations during design reviews in which 8th-grade mathematics students shared population models with visiting specialists expanded the disciplinary expertise of the classroom. "Re-contextualizing" is a conversational exchange that visiting specialists initiated to invite groups to consider their models in novel…

This study focussed on how secondary school students construct and use mathematical models as conceptual tools when solving word problems. The participants were 511 secondary-school students who were in the final year of compulsory education (15-16 years old). Four levels of the development of constructing and using mathematical models were…

Problem. The development of critical-thinking skills during the professional training of respiratory therapists is imperative for good practice. Research evidence suggests that interactive instructional strategies are far more effective than traditional lectures. Missing from the literature are thick descriptions of how faculty organize the…

The partial credit model (PCM) (G. N. Masters, 1982) can be viewed as a generalization of the Rasch model for dichotomous items to the case of polytomous items. In many cases, the PCM is too restrictive to fit the data. Several generalizations of the PCM have been proposed. In this paper, a generalization of the PCM (GPCM), a further…

This discussion of new methods for calibrating item response theory (IRT) models looks into new optimization procedures, such as the Genetic Algorithm (GA) to improve on the use of the Newton-Raphson procedure. The advantages of using a global optimization procedure like GA is that this kind of procedure is not easily affected by local optima and…

In the technique developed by K. G. Joreskog to solve the problem for oblique rotation to a specified simple structure, the basic concept is that the simple structure solution itself is determined only by the zero coefficients of the reference-structure matrix and not by the coefficients of non-zero magnitude. Following this, prior information…

Cross-validation, an economical method for assessing whether sample results will generalize, is discussed in this paper. Cross-validation is an invariance technique that uses two subsets of the data sample to derive discriminant function coefficients. The two sets of coefficients are then used with each data subset to derive discriminant function…

Conditional observed score (COS) and latent trait (LT) definitions of differential item functioning (DIF) are explored to determine when they are equivalent. COS methods rely solely on observed measurements, and LT methods model the response to an item as a function of an unobserved hypothetical latent ability or trait. For the case of dichotomous…

Previous methods for estimating the conditional standard error of measurement (CSEM) at specific score or ability levels are critically discussed, and a brief summary of prior empirical results is given. A new method is developed which avoids theoretical problems inherent in some prior methods, is easy to implement, and estimates not only a…

Trait psychology, psycho-dynamics, situationism, and interactionism, the four basic models of personality, are summarized; controversies they have generated and relevant research are discussed. Special emphasis is placed on interactional psychology as a model of personality theory and research. Controversial issues of personality such as…

The kappamax reliability index of domain-referenced tests is defined as the upper bound of kappa when all possibile cutoff scores are considered. Computational procedures for kappamax are described, as well as its approximation for long tests, based on Kuder-Richardson formula 21. The sampling error of kappamax, and the effects of test length and…

FANTAB is a computer program written in Fortran IV which helps design factorial analysis of variance tables and provides formulae for table entries. It is a computerization of a paper entitled: "Rules of Thumb for Writing the Anova Table" (Millman and Glass, 1967). FANTAB is appropriate for factorial models which have two, three, or four…

Confirms previously published research in concluding that specialty words tend to possess frequency distributions which cannot be described by a single Poisson distribution. (Author/PF)