Interaction in Linear versus Logistic Models: A Substantive Illustration Using the Relationship between Motivation, Ability, and Performance

Abstract
A binary performance measure (high school graduation) is examined as a function of motivation (educational goal), ability (scores in an intelligence test), and their interaction. The interaction was positive when a logistic model was used and negative when a linear probability model was used. The reason for the difference in the results of the two models is examined, and the conditions under which this difference occurs are discussed.