Discusses problems in detecting nonlinear associations and investigates the use of two statistics for this purpose. Simulation results suggest that the Cramer-von Mises form of the test statistic is generally better than the Kolmogorov-Smirnov form. Discusses the power of this method. (SLD)

Examines the use of sample weights in latent variable models in the case where a simple random sample is drawn from a population containing a mixture of strata through a bootstrap simulation study. Results show that ignoring weights can lead to serious bias in latent variable model parameters and reveal the advantages of using sample weights. (SLD)

Investigated Type I error performances of the SIBTEST and Mantel-Haenszel procedures for detecting differential item functioning (DIF) using simulation. Results of small sample simulation show no large differences in Type I error performances for the two techniques. Discusses results of a second simulation which shows some advantages for SIBTEST.…

Examined the sampling distributions of equating coefficients produced by the characteristic curve method for tests using graded and nominal response scoring using simulated data. For both models and across all three equating situations, the sampling distributions were generally bell-shaped and peaked, and occasionally had a small degree of…

Considers P. Schonemann's simulation study in light of the multigroup principal component analysis model and interprets it as a study of the specificity of Spearman correlations, given model violations. Asserts that the Spearman correlation is a suboptimal test of Spearman's hypothesis and contends that an explicit model-based approach should be…

The shape of the latent trait distribution can be of considerable theoretical and methodological importance. A simulation study was performed to examine the distribution of the likelihood ratio statistic that was used to test for normality via Johnson curves, the power to detect deviations from normality, and the estimation properties of the item…

By regarding the latent random vectors as hypothetical missing data and based on the conditional expectation of the complete-data log-likelihood function in the EM algorithm, we investigate assessment of local influence of various perturbation schemes in a nonlinear structural equation model. The basic building blocks of local influence analysis…

Modern video games use physics to achieve realistic behaviour and special effects. Everything from billiard balls, to flying debris, to tactical fighter jets is simulated in games using fundamental principles of dynamics. This article explores several examples of how physics is used in games. Further, this article describes some of the more…

Dodeen (2004) studied the correlation between the item parameters of the three-parameter logistic model and two item fit statistics, and found some linear relationships (e.g., a positive correlation between item discrimination parameters and item fit statistics) that have the potential for influencing the work of practitioners who employ item…

The Internet usage has been increasing among persons in the worldwide. This situation highlights that the number of potential distance learners has been increasing in the Internet society. Besides, the terms and concepts of the Internet environments become to be spread out in this society like virtual reality. It is also possible to explain the…

By having subjects drive a virtual taxicab through a computer-rendered town, we examined how landmark and layout information interact during spatial navigation. Subject-drivers searched for passengers, and then attempted to take the most efficient route to the requested destinations (one of several target stores). Experiment 1 demonstrated that…

This study investigates the extent to which analytic power can be increased through the inclusion of siblings in a data set and the concomitant use of random coefficient multilevel models. Analyses of real-world data regarding the predictors of young adult alcohol use illustrate how parallel single-level analyses of a 1-child-per-family data set…

Gravity is a subtle but ubiquitous force that influences nearly all geologic processes from the formation of ores to the flow of glaciers and rivers. Gravity also determines the path some materials take as they flow down volcanoes. Lava flows, mudflows (also called lahars), and pyroclastic flows are three such materials. Understanding the factors…

The thought of learning about the principles of classical management and the machine metaphor of organizing can get many organizational communication students yawning just by seeing the subject in a syllabus. Abundant movie and television examples associated with the machine-like nature of workplace productivity are often used to demonstrate…

The aim of this activity is to immerse students in a simulated situation where they are enticed to make snap judgments about strangers, demonstrating that they can and easily do, and then motivate them to critically reflect on the consequences that these presumptions have on effective interpersonal communication. This activity allows students to…