Mathematical Models of the Effect of Message Discrepancy on Belief Change: Previous Models and a Modified Psychological Discounting Model

• In Event: HIGH-DENSITY: Exploring Information Systems: Models and Theories

Abstract

Several persuasion researchers have proposed models to predict belief change as a function of message discrepancy. This study compared and evaluated three nonlinear models of the effect of message discrepancy on belief change: a model of message discrepancy with the probability of message acceptance (Fishbein & Ajzen, 1975); a model of belief change by message discrepancy, source credibility, and noninvolvement (Laroche, 1977); and a psychological discrepancy discounting model (Fink, Kaplowitz, & Bauer, 1983). These three models suggest a nonlinear effect of message discrepancy on belief change but are not mathematically derived from the model’s assumptions. This paper proposes a modified psychological discounting model, based on Fink et al.’s and Fishbein and Ajzen’s models, by solving a differential equation about the rate of change of the probability of message acceptance with respect to psychological discrepancy. The new model predicts a monotonically decelerating positive function of message discrepancy on belief change.

Authors

• Sungeun Chung, Sungkyunkwan U

• Edward L. Fink, Temple U