The hypothesis that two variables have a perfect disattenuated correlation and hence measure the same trait, except for errors of measurement, is discussed. Equivalently, the underlying variables, the true scores, are related linearly. It is shown that previously proposed ad hoc tests are, in fact, likelihood ratio tests. (Author/JKS)

The utility of a nonlinear transformation of the criterion variable in multiple regression analysis is established. A well-known law--the Pythagorean Theorem--illustrates the point. (Author/JKS)

Estimators which are optimal under assumptions of normality are shown to be vulnerable to the effects of outliers. A survey of robust alternatives is presented. Included are alternatives to the mean, standard deviation, product-moment correlation, t-test, analysis of variance, multivariate techniques, and schemes for outlier detection. (Author/JKS)

A multiple regression approach is used to assess the feasibility of reciprocal prediction between the Sixteen Personality Factor Questionnaire scales and the California Psychological Inventory scales (i.e., the prediction of each 16PF scale from the CPI scales and of each CPI scale from the 16PF scales). (RC)

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)

This paper shows that redundancy maximization with J. K. Johansson's extension can be accomplished via a simple iterative algorithm based on H. Wold's Partial Least Squares. The model and the iterative algorithm for the least squares approach to redundancy maximization are presented. (TJH)

Using the Life Situation Survey, the perceived quality of life of 100 adults with spinal cord injury was compared with that of 120 adults with mental retardation. Comparison of descriptive statistics and a multiple regression analysis revealed possible differences in the impact of the two disabilities on specific life domains. (JPS)

Compares approaches to modeling ordinal outcome variables, including assumptions, interpretations, and limitations. Explores how the multiple regression approach with ordinal level data can compromise the understanding of the effects of the independent variables and of the ordinal level response. Provides applications with data from a multisite…

Objective: To estimate the impact of arthritis using a general health index and National Health Interview Survey (NHIS) data. Methods: Morbidity data came from NHIS Public Use data, from the years 19861988 and 1994. The data are 423 400 cases, representing 975 421 153 person-years. Quality of Well-being Scale (QWB) morbidity scores were imputed…

Background: An important element of many anti-bullying programmes is encouraging victims to tell someone about their predicament. Research has already reported prevalence of telling, who/when children tell and efficacy of telling. However, seeking help can be viewed as a coping behaviour, and coping processes such as appraisal and emotion may be…

A demonstration, which shows that the graphing calculation can greatly supplement the computer and often eliminates the need for computers and science, is given. The graphic calculator is a handheld computer, more powerful than most sophisticated computer of 25 years ago.

Context: Prior study suggests that contextual characteristics of medical schools (eg, state demographics, public vs private, NIH research effort) predict output of rural physicians without also considering the effects of the medical schools? own policies and programs. Purpose: This study examines medical school commitment to rural policies and…

This article proposes alternative expressions for the two most prevailing definitions of suppression without resorting to the standardized regression modeling. The formulation provides a simple basis for the examination of their relationship. For the two-predictor regression, the author demonstrates that the previous results in the literature are…

The main aim of the study was to evaluate trainee teachers working commitment in their teaching practicum. There were seven component teaching practices and eleven demographic factors. The instrument of the study was extracted from various sources to suit the research design based on Units, Treatments, Observing, and Surveying (UTOS) model…

Understanding and promoting physical activity is critical to combat the growing obesity epidemic in the U.S. This study was designed to compare two 10-week physical activity programs among college students. One hundred and thirty-six undergraduate college students participated in this randomized posttest only control group study. Seventy-seven…