A definition of a suppressor variable is presented which is based on the relation of the semipartial correlation to the zero order correlation. Advantages of the definition are given. (Author/JKS)

Following Conger's revised definition of suppressor variables, the universe relationships among two predictors and a criterion is analyzed. A simple mapping of relationships, based on the correlation between two predictors and the ratio of their validities, is provided. The relation between suppressor and part correlation is also discussed.…

The controversy surrounding regression methods for unbalanced factorial designs is addressed. The statistical hypotheses being tested under the various methods, as well as salient issues in the use of these methods, are discussed. The use of statistical computer packages is also discussed. (Author/JKS)

An artifact encountered in regression models of human judgment is explored. The direction and magnitude of the artifactual effect is shown to depend upon the nature of the experimental task and task conditions. Use of an alternative index is recommended. (Author/JKS)

Paper presents an example of the use of the linear model for attitude measurement emphasizing the validation of the regression weights by comparing them with traditional and more direct measures of attitude. (Author)

The proposed method has the advantage of being a rational procedure which reduces the larger set of variables'' down to a desired subset of predictor variables. The selected subset, then, can be coded for a full regression run if it contains multiple level category variables among those selected. (Author)

Perspective on article by P. Isaac published in the Psychological Bulletin, 1970, 74, 213-18. (CB)

Major objective in this study was the structuring of a predictive model that would assess combinations of variables that most effectively and parsimoniously measure and forecast college success. (Author)

This method of generating multivariate data differs from previous techniques in that it uses Crout factorization to develop the desired variance-covariance matrix. (Author/CK)

Recent theoretical analyses of the concept of suppression are identified and discussed. A generalized definition of suppression is presented and the conditions for suppressor structures in the context of the General Linear Model are derived. (Author)

Eight formula-based estimates of population squared cross-validity and nine estimates of factor scores were compared with estimates from the conventional cross-validation procedure. Burket's and Rozeboom's formula-based estimates of population squared cross-validity in combination with a factor score method offer the most for practitioners…

The use of segmented polynomial models is explained. Examples of design matrices of dummy variables are given for the least squares analyses of time series and discontinuity quasi-experimental research designs. Linear combinations of dummy variable vectors appear to provide tests of effects in the two quasi-experimental designs. (Author/BW)