When repeated observations are taken at equal time intervals, a simple form of a stationary time series structure may be fitted to the observations. Use of correction factors is discussed. A computer simulation method is used to investigate power advantages of fitting a serial correlation pattern to repeated observations. (TJH)

Describes computer simulation programs that take elementary and secondary students exploring. One has students act as Magellan commanding his ship to reinforce history, geography, decision-making, and resource management skills. Another has students use problem-solving skills to venture across oceans and find trading routes to the Orient. (SM)

A graphic, interactive software program that is suitable for teaching students about the measurement and ion dependence of cell membrane potentials is described. The hardware requirements, the aim of the program, how to use the program, other related programs, and its advantages over traditional methods are included. (KR)

Six theme articles address computer-assisted design in landscaping, simulation in agricultural education, Macintosh's HyperCard, computer labs for agribusiness, and using a portable computer to evaluate classroom performance. (SK)

Item parameter estimation errors in test development are highlighted. The problem is illustrated with several simulated data sets, and a conservative solution is offered for addressing the problem in item response theory test development practice. Steps that reduce the problem of capitalizing on chance in item selections are suggested. (SLD)

Discusses computer-based training (CBT) methods that emphasize an interactive learning environment but do not require video. Topics addressed include cognitive processes; different levels of interaction, including simulation or problem solving; the use of icons and buttons; hypertext; differences in learning styles; and thought-provoking…

The sensitivity of marginal maximum likelihood estimation of item and ability (theta) parameters was examined when prior ability distributions were not matched to underlying ability distributions. Thirty sets of 45-item test data were generated. Conditions affecting the accuracy of estimation are discussed. (SLD)

A modification of a test of the equality of nonindependent alpha reliability coefficients is proposed. It avoids the limitation that the product of the number of test parts times the number of subjects be quite large. Monte Carlo studies indicate that this test can be used in comparing interrater reliabilities. (SLD)

Inference is considered for the marginal distribution of "X" when ("X", "Y") has a truncated bivariate normal distribution. The "Y" variable is truncated, but only the "X" values are observed. A sample of 87 Otis test scores is shown to be well described by this model. (SLD)

Describes the structure and operations of a computer simulation model used in Papua New Guinea, developed with technical assistance from UNESCO. Notes that model establishes baseline data on student enrollments, teacher posts, and costs of education, and can be used to simulate policies under consideration and provide output on student flows,…

Describes "Glass-box Interpreter" a low-level program visualization tool called Bradman designed to provide a conceptual model of C program execution for novice programmers and makes visible aspects of the programming process normally hidden from the user. Presents an experiment that tests the efficacy of Bradman, and provides…

Discusses the evaluation of search engines and uses neural networks in stochastic simulation of the number of rejected Web pages per search query. Topics include the iterative radial basis functions (RBF) neural network; precision; response time; coverage; Boolean logic; regression models; crawling algorithms; and implications for search engine…

Reports on a study that examined which of the available simulators could be used by the U.S. Army Armor School (Fort Knox, Kentucky) for instructional purposes and determined actual usage of large-scale simulation networking (SIMNET) by examining usage logs maintained by SIMNET operators. The appendices list Armor School courses and simulators.…

Develops a new model for a process that generates Lotka's Law. Topics include measuring scientific productivity through the number of publications; rate of production; career duration; randomness; Poisson distribution; computer simulations; goodness-of-fit; theoretical support for the model; and future research. (Author/LRW)

Reports the results of research on effects of detailed feedback on problem solving within a computer-based simulation. Participants were 54 undergraduate students. Results indicated highest performance was associated with feedback based on an expert model supplemented with provided textual commentary, suggesting that under some circumstances…