ESTIMATING INDIVIDUAL INFLUENCES OF BEHAVIORAL INTENTIONS - AN APPLICATION OF RANDOM-EFFECTS MODELING TO THE THEORY OF REASONED ACTION

Methods are proposed and described for estimating the degree to which relations among variables vary at the individual level. As an example of the methods, M. Fishbein and I. Ajzen's (1975; I. Ajzen & M. Fishbe in, 1980) theory of reasoned action is examined, which posits first th at an individual's behavioral intentions are a function of 2 component s: the individual's attitudes toward the behavior and the subjective n orms as perceived by the individual. A second component of their theor y is that individuals may weight these 2 components differently in ass essing their behavioral intentions. This article illustrates the use o f empirical Bayes methods based on a random-effects regression model t o estimate these individual influences, estimating an individual's wei ghting of both of these components (attitudes toward the behavior and subjective norms) in relation to their behavioral intentions. This met hod can be used when an individual's behavioral intentions, subjective norms, and attitudes toward the behavior are all repeatedly measured. In this case, the empirical Bayes estimates are derived as a function of the data from the individual, strengthened by the overall sample d ata.