Considerable thought, research, and concern has been expanded in an effort to determine whether the assumption of a quadratic relation between a single predictor and a criterion violated the assumptions which Johnson and Neyman (1936) state for calculating regions of significance about interacting regressions. In particular, there has been special…

Three procedures used to control Type I error rate in stepwise regression analysis are forward selection, backward elimination, and true stepwise. In the forward selection method, a model of the dependent variable is formed by choosing the single best predictor; then the second predictor which makes the strongest contribution to the prediction of…

Discriminant analysis is reviewed in terms of: (1) formulations, (2) interpretations, (3) uses, (4) issues and problems in applications, (5) recent developments and conceptualizations, and (6) general references and computer programs. Four aspects of a discriminant analysis are considered. They are: (1) separation: determining intergroup…

Joreskog has developed a very general and powerful model and computer program for analyzing relationships among variables, called LISREL. Structural analysis of covariance matrices by Joreskog's LISREL method is proposed as an alternative to regression methodology in the analysis of aptitude-treatment interaction (ATI) data. LISREL resolves some…

This document presents a modified cohort survival model which can be of use in making enrollment projections. The model begins by analytically profiling an area's residents. Each person's demographic characteristics--sex, age, place of residence--are recorded in the computer memory. Four major input variables are then incorporated into the model:…