A bivariate generalization of the genotype-environment covariation (GEC) is presented. A multivariate procedure for detecting univariate and bivariate GEC is also described and illustrated via a study of 136 adopted and 125 non-adopted 4-year-old children. (SLD)

Single sample approximations are considered for the cross-validation coefficient in the analysis of covariance structures. Results of a random sampling experiment--using data from ability tests administered to high school students (sample sizes 100, 400, and 800)--illustrate the coefficient and adjustment for predictive validity. (SLD)

A method for detecting instructional sensitivity (item bias) in test items is proposed. This method extends item response theory by allowing for item-specific variation in measurement relations across students' varying instructional backgrounds. Item bias detection is a by-product. Traditional and new methods are compared. (SLD)

A model is presented for the growth of knowledge reflected by 24 progress tests completed by approximately 600 students at the University of Limburg (Netherlands) Medical School. Based on the Rasch model, this model treats both the person's ability and the difficulty of the question as random variables. (SLD)

An alternative to the Rasch model is introduced. It characterizes strength of response according to the ratio of ability and difficulty parameters rather than their difference. Joint estimation and marginal estimation models are applied to two test data sets. (SLD)

Statistical significance and "abnormality" have been used as criteria for the evaluation of intra-individual subtest score differences. Shortcomings of these criteria are identified, and improved estimates of the true score differences are suggested. The applicability of the abnormality criterion to these improved estimates is reviewed.…

Summarizes a reanalysis of the data from an investigation of a test designed to measure a learning sequence in geometry based on the work of van Hiele (1986). Discusses the test based on the Rasch model. (YP)

A group of covariance structure models was examined to ascertain the similarity between conventionally administered and computerized adaptive versions of the Differential Aptitude Test (DAT). Results for 332 students indicate that the computerized version of the DAT is an adequate representation of the conventional test battery. (TJH)

Investigates the potential for carry-over of prior learning from one scenario to the next at various parts of the hard-soft spectrum in a control engineering context. Discusses hard-soft systems, input-output analysis, law of industrial dynamics, decision-making, developing models, model sensitivity analysis, and educational programs. (YP)

Describes the spectrum of process design problems. Suggests a methodology for teaching some concepts used in design, including the types of processes considered and their designs, new tools useful in conceptual design, and a strategy for developing conceptual designs. (YP)

Multinomial modeling--a methodology that can be used to measure and study cognitive processes--is discussed, and applications are presented. This statistically based technique involves estimating hypothetical parameters that represent the probabilities of unobservable cognitive events and is compatible with computational theories of cognition.…

This instructional module discusses the one-, two-, and three-parameter logistic item response theory (IRT) models. Mathematical formulas are given for each model and they are compared, with figures illustrating the effects of changing parameters. A single data set is used to demonstrate the effects of changing parameter values. (SLD)

Contrary to assumptions of the supergame model, agents in exchange situations will normally not be perfectly informed about past behavior of their partners. Moreover, they will generally be in a position to choose their partners. The formal model of this article, reputation formation, attempts to take account of these facts. (JBJ)

Enrollment managers in search of a flexible, comprehensive student flow model will find the Markov Chain a suitable mathematical process for use in tracking students through their academic careers. Furthermore, projections can be made based on previous enrollment patterns, and many scenarios can be examined under various constraints and…

The Core-Plus Mathematics Project (CPMP) is a four-year program emphasizing mathematical modeling, featuring full use of graphing calculators, building on the theme of mathematics as sense-making, and involving investigations of real-life contexts that lead to reinventing important mathematics. (MKR)