The present paper discusses criticisms of statistical significance testing from both historical and contemporary perspectives. Statistical significance testing is greatly influenced by sample size and often results in meaningless information being over-reported. Variance-accounted-for-effect sizes are presented as an alternative to statistical…

One set of approaches to the problem of clustering with dichotomous data in cluster analysis (CA) was studied. The techniques developed for clustering with binary data involve calculating distances between observations based on the variables and then applying one of the standard CA algorithms to these distances. One of the groups of distances that…

Derived a confidence interval for a ratio of correlated mean absolute deviations. Simulation results show that it performs well in small sample sizes across realistically nonnormal distributions and that it is almost as powerful as the most powerful test examined by R. Wilcox (1990). (SLD)

Recent simulations have shown that, for a given sample size, the Mantel-Haenszel (MH) variances tend to be larger when items are administered to randomly selected examinees than when they are administered adaptively. Results suggest that adaptive testing may lead to more efficient application of MH differential item functioning analyses. (SLD)

An analysis of repeated measures designs is proposed that uses an empirical Bayes estimator of the covariance matrix. The proposed analysis behaves like a univariate analysis when sample size is small or sphericity nearly satisfied, but behaves like multivariate analysis when sample size is large or sphericity is strongly violated. (SLD)

Explores the asymptotic theory of a method of nonparametric item characteristic curve estimation based on kernel smoothing with the theory of obtaining the proper linear ordering of examinees with respect to their true latent abilities. Results support the usefulness of estimates of the type produced by the TESTGRAF program. (SLD)

Estimated Type I error rates and power are reported for six tests of variance. Normal and non-normal distributions of a two-group design were investigated. Tests developed by M. B. Brown and A. B. Forsythe and by R. G. O'Brien were considered most useful. Implications are discussed. (SLD)

A longitudinal factor analysis model that is entirely exploratory is proposed for use with multiple populations. Factorial collapse, period/practice effects, and an invariant and/or stationary factor pattern are allowed. The model is formulated stochastically and implemented via a stage-wise EM algorithm. (TJH)

Alternative strategies for two-sample cross-validation of covariance structure models are described and investigated. Results of an empirical sampling study show that for tighter strategies simpler models are preferred in smaller samples, but when cross-validation is employed, a more complex model is supported even for small samples. (SLD)

Briefly reviews illustrative literature on willingness or unwillingness of older adults to participate in clinical trials, health promotion/disease prevention initiatives, and health programs to maintain or improve functioning of chronically ill older adults. Review provides overview of participation of older adults in health programs and…

Single-case study examined frank disclosure of important topics in brief exploratory psychotherapy, including topics closely related to recent, unintegrated stressor life event. Quantitative measures of emotion and control variables showed heightened levels of both emotionality and defensive control during discourse on topic of stressor event.…

Clarifies several issues regarding the effects of autocorrelated errors on Type I error in ordinary least-squares models. Demonstrates through Monte Carlo simulation the conditions under which distortion in Type I error is less than predicted by asymptotic theory. Suggests a recently developed small-sample method for time-series analyses. (SLD)

Studied results from five linking methods under the graded-response model using simulated data. Results show that differences in the linking coefficients are small. The five methods yielded similar results for longer common-item links with large sample sizes and when the distribution of item-location parameters matched the underlying trait…

This study developed a testing approach to increase sample size to approximately 450 scorable items, previously determined as necessary to optimize the reliability of a speech recognition test. The approach involves an interactive computer program which presents words in 50 three-word groups. The approach was evaluated with 100 persons with normal…