Used Monte Carlo methods to evaluate the adequacy of cluster analysis to recover group membership based on simulated latent growth curve (LCG) models. Cluster analysis failed to recover growth subtypes adequately when the difference between growth curves was shape only. Discusses circumstances under which it was more successful. (SLD)

Points out two concerns with recent research by F. Li and others (2000) and T. Duncan and others (1999) that extended the structural equation model of latent interactions developed by K. Joreskog and F. Yang (1996) to latent growth modeling. Used mathematical derivation and a comparison of alternative models fitted to simulated data to develop a…

Studied two procedures for detecting potentially flawed items in translated tests with small samples: (1) conditional item "p" value comparisons; and (2) delta plots. Varied several factors in this simulation study. Findings show that the two procedures can be valuable in identifying flawed test items, especially when the size of the…

Examines instructional computer simulation from a Heideggerian point of view, claiming that traditional conceptions of simulation do not account for important characteristics of existence, namely anxiety and waiting. Discusses Heidegger's conception of Bestand, or standing reserve, and suggests implications for instruction. (Author/LRW)

Compared the analysis of variance (ANOVA) "F" and several nonparametric competitors for two-way designs for empirical alpha and power through simulation. Results suggest the ANOVA "F" suffers from conservative alpha and power for the mixed normal distribution, but is generally recommended. (Author/SLD)

Studied the effect on criterion-related validity of nonfitting response vectors (NRVs) on a predictor test using simulation. Results suggest that NRVs can influence the validity of a test if the type of misfit is severe, the correlation between the predictor and criterion scores is "p"=0.3 or 0.4, and there are 15% or higher NRVs. (SLD)

Discussion of the four basic types of educational simulators that are available foe medical education for problem-based, interactive learning focuses on the role of microsimulators. Describes educational medical simulators and suggests that the development of microsimulators should focus on the intelligent, educational feedback in the debriefing.…

Presents a variable selection heuristic for nonhierarchical (K-means) cluster analysis based on the adjusted Rand index for measuring cluster recovery. Subjected the heuristic to Monte Carlo testing across more than 2,200 datasets. Results indicate that the heuristic is extremely effective at eliminating masking variables. (SLD)

Describes a class of rater effects, differential rater functioning over time (DRIFT), that depicts rater-by-time interactions. Also describes Rasch measurement procedures designed to identify these types of DRIFT in rating data. Applied these procedures to simulated data to show their usefulness in classifying raters as aberrant or non-aberrant…

Examined the use of the generalized graded unfolding model (GGUM) in computerized adaptive testing, using simulation and attempting to minimize the number of items required to produce equiprecise estimates of person locations. Results suggest that adaptive testing with the GGUM is a good method for achieving estimates with an approximately uniform…

Used logistic regression to model the observation-to-variable ratio required for the standard error scree procedure to identify the number of factors in simulated data correctly. Results demonstrate the ability of logistic regression to simplify summarizing and reporting findings from simulation studies that involve a large number of conditions.…

Explains a simulation that can be used effectively to introduce the concept of dynamic equilibria. (Contains 19 references.) (YDS)

Presents results of a study designed to determine effects of schooling and health knowledge on probability of men and women becoming obese. Findings indicate that schooling, but not health knowledge, reduces the probability of male and female obesity. (Contains 29 references.) (PKP)

Conventional wisdom in missing data research dictates adding variables to the missing data model when those variables are predictive of (a) missingness and (b) the variables containing missingness. However, it has recently been shown that adding variables that are correlated with variables containing missingness, whether or not they are related to…

The purpose of this study was twofold: (a) to determine the extent to which 4-channel, slow-acting wide dynamic range amplitude compression (WDRC) can counteract the perceptual effects of reduced auditory dynamic range and (b) to examine the relation between objective measures of speech intelligibility and categorical ratings of speech quality for…