Describes virtual realities as environments in which visual, aural, or other stimuli generate in the mind of the user a sense of navigable, frameless, three-dimensional space, and predicts that the availability of computer technology to create real-time, three-dimensional graphics will bring radical changes in the educational use of visualization…

The algorithm developed by B. A. Schneider (1980) for analysis of paired comparisons of psychological intervals is replaced by one proposed by R. M. Johnson. Monte Carlo simulations of pairwise dissimilarities and pairwise conjoint effects show that Johnson's algorithm can provide good metric recovery. (SLD)

Describes the "Virtual Cities" project, a virtual reality satellite teleconference with students age 12 to 17 from Canada, Italy, and the United States held during the International Council for Educational Media 1992 conference. A visual database overlaid with instructional gaming strategies provided students with the opportunity to…

Describes a project that explores the use of interactive computer software for teaching Einstein's special theory of relativity to secondary students. Also describes ways to use computers to help students visualize and experiment with otherwise inaccessible phenomena. (ZWH)

The present simulation study confirms that the corrected epsilon approximate test of B. Lecoutre yields a less biased estimation of population epsilon and reduces Type I error rates when compared to the epsilon approximate test of H. Huynh and L. S. Feldt. (SLD)

New methods for comparing the medians corresponding to independent treatment groups are suggested. Procedures are based on the estimator of F. Harrell and C. Davis in conjunction with a modification and extension of the bootstrap calibration technique suggested by W. Loh. Data from two groups provide an illustration. (SLD)

A statistical method, W. F. Stout's statistical test of essential unidimensionality (1990), for exploring the lack of unidimensionality in test data was studied using Monte Carlo simulations. The statistical procedure is a hypothesis test of whether the essential dimensionality is one or exceeds one, regardless of the traditional dimensionality.…

A Monte Carlo study, which simulated 10,000 examinees' responses to four tests, investigated the effect of item stratification on parameter estimation in multiple matrix sampling of achievement data. Practical multiple matrix sampling is based on item stratification by item discrimination and a sampling plan with moderate number of subtests. (SLD)

A method is presented that eliminates some interpretational limitations arising from assumptions implicit in the use of arbitrary rules of thumb to interpret exploratory factor analytic results. The bootstrap method is presented as a way of approximating sampling distributions of estimated factor loadings. Simulated datasets illustrate the…

A mathematical formula is introduced for the effect of integrating data. A method is then derived to eliminate the effect from correlations of variables, including mean composites, thus allowing for a clustering algorithm that requires allocation of variables according to the magnitude of their correlations. Examples illustrate the procedure. (SLD)

Demonstrated is the use of BASIC computer programs to simulate a binomial experiment and test a simple statistical hypothesis. The theoretical results are reached with the third programing attempt. All results, as well as computer programs, are included. (JJK)

SimuFlite Co. nearly went under when a state-of-the-art computer-based training simulation for airplane pilots took too long to develop and was not liked by participants. The revamped program emphasized live instructors, technical manuals, and videotapes. The program's failure illustrates the disadvantages of computer-based training. (SK)

Describes various electronic technologies available for classroom use, including videocassette news reports, educational computer games based on knowledge of geographical and historical trivia, and other software programs developed expressly for schools. Nintendo Company is being watched for optical disk developments, and "virtual…

Simulation studies (N=4,000 simulees) examined the effect of misspecification of the latent ability distribution (theta) on the accuracy and efficiency of marginal maximum likelihood (MML) item parameter estimates and on MML statistics to test sufficiency and conditional independence. Results were compared to those of the conditional maximum…

The standard error (SE) of correlations adjusted for selection with commonly used formulas was investigated. The study provides large-sample approximations of SE using the Pearson-Lawley three-variable correction formula, examines the SE under specific conditions, and compares various estimates of SEs under direct and indirect selection. (TJH)