This study was designed to derive the distribution of a test statistic based on normal probability plots. The first purpose was to provide an empirical derivation of the critical values for the Line Test (LT) with an extensive computer simulation. The goal was to develop a test that is sensitive to a wide range of alternative distributions,…

To determine the effect of violating the assumption of homogeneity of covariance for the Tukey Wholly Significant Difference (WSD) test, Monte Carlo simulations varied the number of treatment groups, sample size, and degree of covariance heterogeneity. As covariance heterogeneity was increased, the empirical significance levels increased beyond…

Monte Carlo methods are used to explore the accuracy of a method for establishing confidence intervals for variance component estimates in generalizability studies. Previous research has shown that variance component estimation errors due to sampling are often larger than suspected. (Author/CM)

Three methods of handling disproportionate cell frequencies in two-way analysis of variance are examined. A Monte Carlo approach was used to study the method of expected frequencies and two multiple regression approaches to the problem as disproportionality increases. (Author/JKS)

A Monte Carlo simulation evaluated conditions that contribute to excessively high coefficients of congruence when fitting one factor pattern matrix into the space of a targeted pattern. Results support the conclusion that orthogonal Procrustes methods of factor rotation do produce spurious coefficients between predictor and criterion factor…

A convention commonly used to describe interaction effects within moderated regression frameworks was examined through logical exposition and a Monte Carlo approach to simulate various moderator conditions. Results, which indicate that the convention may lead to incorrect inferences, are discussed in terms of interpreting moderator effects. (SLD)

A general approach to least-squares unidimensional scaling is presented. Ordering information contained in the parameters is used to transform the standard squared error loss function into a discrete rather than continuous form. Monte Carlo tests with 38,094 ratings of 261 senators, and 1,258 representatives demonstrate the procedure's…

A simulation study compares nonhierarchical clustering capabilities of a class of neural networks using Kohonen learning with a K-means clustering procedure. The focus is on the ability of the procedures to recover correctly the known cluster structure in the data. Advantages and disadvantages of the procedures are reviewed. (SLD)

This paper presents a new procedure called TREEFAM for estimating ultrametric tree structures from proximity data confounded by differential stimulus familiarity. The objective is to quantitatively filter out effects of stimulus unfamiliarity. Superiority of TREEFAM over conventional methods is illustrated through a Monte Carlo study and an…

Effectiveness of jackknife methods in reducing bias in estimation of the log-1 autocorrelation parameter p1 was evaluated through a Monte Carlo study using sample sizes ranging from 6 to 500. These estimates appear less biased in the small sample case than many that have been investigated recently. (SLD)

Monte Carlo studies were conducted to compare four multivariate analysis of variance (MANOVA) simultaneous test procedures (STPs) in terms of power and Type I error under various conditions including violations of MANOVA assumptions. Results do not support the hypothesis that the moderately restricted STP is a good compromise between…

Demonstrates Markov chain Monte Carlo (MCMC) techniques that are well-suited to complex models with Item Response Theory (IRT) assumptions. Develops an MCMC methodology that can be routinely implemented to fit normal IRT models, and compares the approach to approaches based on Gibbs sampling. Contains 64 references. (SLD)

Used Monte Carlo simulations to compare Type I error rates and the statistical power of three tests in detecting the effects of a dichotomous moderator variable in meta-analysis. The highest statistical power was shown by the Zhs test proposed by J. Hunter and F. Schmidt (1990). Discusses criteria for selecting among the three tests. (SLD)

Investigated the performance of the Poly-DIMTEST (PD) procedure (and associated computer program) in assessing the unidimensionality of test data produced by polytomous items through Monte Carlo simulation. Results show that PD can confirm unidimensionality for unidimensional simulated data and can detect lack of unidimensionality. (SLD)

This research is an empirical study, through Monte Carlo simulation, of the effects of violations of the assumptions for the oneway fixed-effects analysis of variance (ANOVA) and analysis of covariance (ANCOVA). Research reaffirms findings of previous studies that suggest that ANOVA and ANCOVA be avoided when group sizes are not equal. (SLD)