Examined use and interpretation of logistic regression in leading higher education journals. Found increasingly sophisticated use for a wide range of topics; however, there continued to be confusion over terminology. Sample sizes did not always achieve a desired level of stability in parameters estimated, and discussion of results in terms of…

Discusses regression toward the mean and the confusion this can cause in the interpretation of educational data. The regression effect has two causes, imperfect measurement of the variables and imperfect correlation between the variables. Uses the example of reading achievement test scores in a Hawaiian private school to illustrate the discussion.…

Most introductory textbooks on simple linear regression analysis mention the fact that extreme data points have a great influence on ordinary least-squares regression estimation; however, not many textbooks provide a rigorous mathematical explanation of this phenomenon. Suggests a way to fill this gap by teaching students the concept of breakdown…

Introduces a computer package written for Mathematica, the purpose of which is to perform a number of difficult iterative functions with respect to the squared multiple correlation coefficient under the fixed and random models. These functions include computation of the confidence interval upper and lower bounds, power calculation, calculation of…

The authors argue that the textbook treatments of the constant term in regression analysis vary extensively and are often neglectful, incomplete, or even incorrect. Given the potential importance of the constant coefficient in theoretical and applied work, they develop the factors biasing the estimation of the constant term to support the argument…

Objective: To examine whether children with substantiated maltreatment reports between 4 and 8 years of age differ from children with unsubstantiated reports on any of 10 behavioral and developmental outcomes. Method: Longitudinal data from 806 children and their adult caregivers collected in four US study sites were pooled and analyzed using…

Differences in rates of case closure, case service cost, hours worked per week, and weekly wage between customers with autism closed successfully in competitive employment and supported employment were found using the Rehabilitation Service Administration national database of 2001. Using logistic regression, customer demographic variables related…

Focusing on a single sample obtained randomly with replacement from a single population, this article examines the regression of population on sample proportions and develops an unbiased estimator of the square of the correlation between them. This estimator turns out to be the regression coefficient. Use of the squared-correlation estimator as a…

A simplified mathematical model for the calculation of imprecision associated with the construction of a calibration line is presented. The model also aims at a discussion on variables that really affect it and to integrate the resulting imprecision with that caused by the other steps in the analytical method in order to calculate a real…

This study developed algorithms for predicting activity energy expenditure (AEE) in children (n = 24) and adults (n = 24) from the Actical[R] activity monitor. Each participant performed 10 activities (supine resting, three sitting, three house cleaning, and three locomotion) while wearing monitors on the ankle, hip, and wrist; AEE was computed…

Background:: Child maltreatment is prevalent in Canadian society, and medical professionals are frequently required to provide care in these cases. Physician knowledge and training in child protection have been questioned. This study examined the experience, perceived adequacy of training, and perceived competency of Canadian pediatric residents…

This article builds on the previous article by Blitstein et al. (2005), which showed how external estimates of intraclass correlation can be used to improve the precision for the analysis of an existing group randomized trial. The authors extend that work to sample size estimation and power analysis for future group-randomized trials. Often this…

Blanton and Jaccard questioned the 4-test regression method used by Greenwald et al. to test a pure multiplicative theory. The present authors address Blanton and Jaccard's concerns with a combination of simulations and meta-analysis. Simulations show that (a) Blanton and Jaccard's preferred simultaneous regression method has a severe power loss…

Some simple, nonoptimized coefficients (e.g., correlation weights, equal weights) were pitted against regression in extensive prediction competitions. After drawing calibration samples from large supersets of real and synthetic data, the researchers observed which set of sample-derived coefficients made the best predictions when applied back to…

In multilevel regression, centering the model variables produces effects that are different and sometimes unexpected compared with those in traditional regression analysis. In this article, the main contributions in terms of meaning, assumptions, and effects underlying a multilevel centering solution are reviewed, emphasizing advantages and…