Developed a method, based on the conditional maximum likelihood principle, for establishing latent change classes in dichotomous data. Simulation studies and a real data set from an earlier study illustrate the method of parameter estimation. (SLD)

Developed methods for testing whether or not patterns of incomplete data represent samples from a single population. Results from a simulation study show that the generalized least squares test of homogeneity of means performed close to an ideal Type I error rate for most of the conditions. The generalized least squares test of homogeneity of…

Studied the statistical properties of the K-index (P. Holland, 1996) that can be used to detect copying behavior on a test through a simulation study of the use of the K-statistic with small, medium, and large datasets. Also compared the Type I error rate and detection rate of this index with those of the copying index (J. Wollack, 1997).…

Through simulation, showed that a multivariate test of interactions for aligned ranks in a split-plot design controlled Type I error rates for nonnormal data with nonspherical covariance structures. This method also performed well in the presence of a strong repeated measures main effect and demonstrated more statistical power than parametric…

Results of this simulated study indicate that, when unidimensional stimulus sets are scaled in two dimensions using a rational starting configuration, the nature of the two-dimensional configuration can indicate the general form of the function mapping psychological dissimilarity--represented as distance in the scaling model--onto the observed…

Simulated test data (N=864 artificial data sets) with four different error conditions were used to study the recovery characteristics of the beta-flexible clustering method. Conditions under which the beta-flexible method provides good recovery are discussed. (SLD)

Three-dimensional response surface plots are presented for several hierarchical clustering methods and simulated core group data structures. Influence patterns explain some results from previous validation research on clustering methods and have significant implications for the choice of clustering methods in empirical research. (SLD)

In Varimax rotation, permutations and reflections can give rise to the phenomenon that certain pairs of columns are consistently skipped in the iterative process, causing Varimax to terminate at a nonstationary point. This skipping phenomenon is demonstrated, and how to prevent it is described. (SLD)

Fundamental concepts of Gaussian Recognition Theory are reviewed, and one of the major theorems used to test for perceptual independence among stimulus dimensions is disputed through a relatively simple counterexample. An amended version of the theorem, Theorem 4, is offered, and a simulation demonstrates its utility. (SLD)

Business simulation can give everyone a fresh overview of the business. Well-designed games and simulations can help players understand why change is necessary and can create within the learner a demand for know-how that no lecture can match. (JOW)

A theoretical four-mass model of the larynx was developed to simulate laryngeal biomechanical behavior and used to evaluate states of asymmetric laryngeal vibration. Simulations of laryngeal paralyses were compared with data on glottal vibration in observed laryngeal function. (Author/JDD)

Differences between per experiment (PE) and experimentwise (EW) error rates were studied through simulation for several multiple-comparison procedures for both pairwise comparisons and planned contrasts. Results suggest ways to control PE rates through new multiple-comparison procedures that maximize experimental power while controlling Type I…

Results from a simulation study confirm that under reasonably representative conditions the replication demonstrated by clustering mean profiles from several preliminary cluster analyses of independent subsets of multivariate profiles is an adequate criterion for inferring the correct number of underlying populations when they are reasonably well…

This article shows that D. L. Hintzman's criticism of the Tulving-Wiseman function is based on an unjustified assumption that is implicit in his simulation procedure, an assumption that is at variance with empirical facts. A more appropriate hypothesis makes the discrepancy between average maximum and algebraic maximum disappear. (SLD)

Explores the concept of validity in relation to games and simulations, including four aspects of validity that apply to simulations and games (psychological reality, structural validity, process validity, and predictive validity). Factors that may threaten validity during game design are discussed, and suggestions are made to avert these threats.…