The polytomous unidimensional Rasch model with equidistant scoring (rating scale model) is extended so that two parameters are linearly decomposed into certain basic parameters. A conditional maximum likelihood estimation procedure and a likelihood ratio test are presented in the context of the extended model (linear rating scale model). (SLD)

Describes computer software intended to help students understand the factors that determine their risk of HIV infection (ZWH)

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)

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)

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)

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…

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)

Advocates using computer-simulated learning environments to allow students to develop their own problem-solving rules when it comes to collecting and evaluating scientific data. Describes the use of "Identibacter interactus" to simulate identification of an unknown microorganism. (WRM)

Describes the human patient simulator and discusses the value of this technology for undergraduate and graduate nursing education, research, and evaluation. Highlights include an example of the use of the simulator; critical incident nursing management as a framework for instruction using the simulator; and administrative considerations. (LRW)

Teachers have always dreamed of taking their students to visit faraway places, or traveling with them to bygone days. Now, through the power of technology, students can experience "virtually" other times and places through "distance learning." The Internet, satellite communications, television, and telephones can provide access to some exceptional…

Film and media courses appear well placed to exploit technology convergence in exposing students both to practical skills and to theoretical concepts. For the University of Cape Town's (UCT) large film and media studies courses, it is impractical simply to use the technology of professionals as this would typically be too expensive to purchase and…

Although computer modelling is widely advocated as a way to offer students a deeper understanding of complex phenomena, the process of modelling is rather complex itself and needs scaffolding. In order to offer adequate support, a thorough understanding of the reasoning processes students employ and of difficulties they encounter during a…

While learning a complex skill in science using a computer-based simulation, optimal timing of information presentation facilitates learning and enhances test performance. An optimal information presentation format is proposed: supportive information is presented before practising a skill, and procedural information is presented during practice.…