Questionnaires inquiring about psychopathology symptoms often produce data with excess zeros or the equivalent (e.g., none, never, and not at all). This type of zero inflation is especially common in nonclinical samples in which many people do not exhibit psychopathology, and if unaccounted for, can result in biased parameter estimates when…

A review of the development of canonical correlation is presented and insufficiencies in applications from the literature are summarized. A list of analytical procedures for use in canonical correlation is detailed. The relationship between analysis and interpretation is emphasized. An example is presented. (JKS)

The degree of indeterminacy of the factor score estimates is biased and can lead to erroneous conclusion regarding the nature of the results. The magnitude of this bias is illustrated and guidelines for describing factor analytic studies using factor scores are offered. (Author/PN)

Basic rules are suggested to replace the signed coefficient rule to infer the form of moderator effects in terms of slopes of regression lines. Steps are provided to interpret the form of moderator effects that can be achieved using only the regression coefficients of the predictor variable and interaction term. (SLD)