Proposed a new asymptotic formula for estimating the sampling variance of a correlation coefficient corrected for unreliability and range restriction. A Monte Carlo simulation study of the new formula results in several positive conclusions about the new approach. (SLD)

Bootstrap methodology is presented that yields approximations of the sampling variation of redundancy estimates while assuming little a priori knowledge about the distributions of these statistics. Results of numerical demonstrations suggest that bootstrap confidence intervals may offer substantial assistance in interpreting the results of…

Sampling theory for the intraclass reliability coefficient, a Spearman-Brown extrapolation of alpha to a single measurement for each examinee, is less recognized and less cited than that of coefficient alpha. Techniques for constructing confidence intervals and testing hypotheses for the intraclass coefficient are presented. (SLD)

Examined Type I error rates and power for four tests for treatment control studies in which a larger treatment mean may be accompanied by a larger treatment variance and examined these aspects of the independent samples "t" test and the Welch test. Evaluated each test and suggested conditions for the use of each approach. (SLD)

This study utilized a rating scale and random sampling of Connecticut school speech-language pathologists about their preprofessional education and current knowledge of autism spectrum disorders (ASD). The participants had a minimal amount of preprofessional academic or clinical preparation in ASD, and no differences were found in how…

Measurement error is a common theme in classical measurement models used in testing and assessment. In classical measurement models, the definition of measurement error and the subsequent reliability coefficients differ on the basis of the test administration design. Internal consistency reliability specifies error due primarily to poor item…

The technique of distance sampling is widely used to monitor biological populations. This paper documents an in-class activity to introduce students to the concepts and the mechanics of distance sampling in a simple situation that is relevant to their own experiences. Preparation details are described. Variations and extensions to the activity are…

Reporting methods used in large-scale assessments such as the National Assessment of Educational Progress (NAEP) rely on latent regression models. To fit the latent regression model using the maximum likelihood estimation technique, multivariate integrals must be evaluated. In the computer program MGROUP used by the Educational Testing Service for…

This article demonstrates the use of mixed-effects logistic regression (MLR) for conducting sequential analyses of binary observational data. MLR is a special case of the mixed-effects logit modeling framework, which may be applied to multicategorical observational data. The MLR approach is motivated in part by G. A. Dagne, G. W. Howe, C. H.…

Randomized controlled trials in educational research tend to be small. Small trials can have large, chance, imbalances in important covariates. For studies with sample sizes greater than 50, chance imbalances can be corrected using analysis of covariance; for small trials, however, statistical power is maximized if the trial is balanced and…

This article describes the development and initial psychometric properties of the Milwaukee Inventory for Styles of Trichotillomania-Child Version (MIST-C), a self-report scale designed to assess styles of hair pulling in children and adolescents diagnosed with trichotillomania (TTM). Using Internet sampling procedures, the authors recruited 164…

This paper provides practical guidance for researchers who are designing studies that randomize groups to measure the impacts of interventions on children. To do so, the paper: (1) provides new empirical information about the values of parameters that influence the precision of impact estimates (intra-class correlations and R-squares); (2)…

The purpose of this study was to examine the correlation between online survey non-response and various demographic factors, including gender. Studies have shown that trends exist with regard to who responds to surveys, at least with regard to traditional modes of survey administration. Reports suggest that many demographic and other correlates…

Although there is evidence of parental participation in school governance in South Africa, the question of how these parents manage their participation in these affairs is largely unanswered. This question represents one of the major exclusions in the existing reflections on the school governance debate in the country. Using a qualitative…

Three years of graduating business honors cohorts in a large urban university were sampled to determine whether the introduction of ubiquitous laptop computers into the honors program contributed to student achievement, student satisfaction and constructivist teaching activities. The first year cohort consisted of honors students who did not have…