Valid assessment of professional competence has proven to be an elusive goal. Objective tests, direct observation of performance, overall ratings of competence, and simulations have been tried and found wanting in one way or another. Objective test items are criticized as being unrealistic and therefore invalid. Direct observation tends to be very…

An attempt was made to determine which item response theory (IRT) equating method results in the least amount of equating error or "scale drift" when equating scores across one or more test forms. An internal anchor test design was employed with five different test forms, each consisting of 30 items, 10 in common with the base test and 5…

The feasibility of quick norms derived by the procedure described by B. D. Wright and M. H. Stone (1979) was investigated. Norming differences between traditionally calculated means and Rasch "quick" means were examined for simulated data sets of varying sample size, test length, and type of distribution. A 5 by 5 by 2 design with a…

The essence of the computer revolution is yet to come, for computers are essentially generators of realities. Virtual reality (VR) is the next step in the evolutionary path; the user is placed inside the image and becomes a participant within the computational space. A VR computer generates a direct experience of the computational environment. The…

Previous work on the effects of dimensionality on parameter estimation was extended from dichotomous models to the polytomous graded response (GR) model. A multidimensional GR model was developed to generate data in one-, two-, and three-dimensions, with two- and three-dimensional conditions varying in their interdimensional associations. Test…

The appallingly inadequate knowledge of current and international affairs among U.S. college students is well documented. ICONS, the International Communication and Negotiation Simulations program, offers an encouraging initiative for addressing the problem. ICONS is a "model United Nations" that the staff of the University of Maryland…

A typology of role-playing and simulation exercises based on interpersonal interactions, used in second language instruction, is presented. Ten dimensions of such simulations were identified, which can then be used as criteria for classifying the exercises. The dimensions include: the starting point of the simulation; complexity of the…

Car Builder is a scientific CD-ROM-based simulation program that lets students design, construct, modify, test, and compare their own cars. Students can design sedans, four-wheel-drive vehicles, vans, sport cars, and hot rods. They may select for aerodynamics, power, and racing ability, or economic and fuel efficiency. It is a program that teaches…

The effectiveness of computer simulation versus laboratory procedures in teaching logic circuits was compared. Also investigated was the sequencing of these activities with a reading assignment. Subjects were 96 undergraduates who were tested using different pretests and posttests. An analysis of variance on the data gathered showed that sequence…

This study compared the model of J. E. Grizzle, C. F. Starmer, and G. G. Koch (GSK, 1969) and log-linear model-based approaches for testing hypotheses in r x c contingency tables. Tables were simulated under various conditions of table, sample, row-effect size, and column-effect size. Test statistics for column (main) and interaction effects were…

P. O. Johnson and J. Neyman (1936) proposed a general linear hypothesis testing procedure for testing the null hypothesis of no treatment difference in the presence of some covariates. This is generally known as the Johnson-Neyman (JN) technique. The need for the hypothesis testing step (often omitted) as originally presented and the…

This paper examines how temporal and spatial observation variables can drastically alter a visitor's comprehension of the phenomena depicted by a museum exhibit. The focus is on a tornado exhibit at the Exploratorium, a museum of science and human perception in San Francisco (California). Videotaped recordings of 10 children interacting with the…

This study investigated the robustness of the James second-order test (James 1951; Wilcox, 1989) and the univariate F test under a two-factor fixed-effect analysis of variance (ANOVA) model in which cell variances were heterogeneous and/or distributions were nonnormal. With computer-simulated data, Type I error rates and statistical power for the…

By definition, differential item functioning (DIF) refers to unequal probabilities of a correct response to a test item by examinees from two groups when controlled for their ability differences. Simulation results are presented for an attempt to purify a test by separating out multidimensional items under the assumption that the intent of the…

Science and technology are often presented and taught as two separate essences. When this is done, students as well as teachers are forced to attempt to develop the appropriate linkages. This book is one of a series designed to help teachers develop their science and technological education in ways that are both satisfying to themselves and…