Behavioral variability as a function of people, situations, and their interaction.

Behavioral variability has long been a central topic in personality psychology. Traditionally, research has focused on differences in mean levels of behavior across situations and time, rather than taking a situation-specific approach to variability. These approaches neglect variability (or the opposite, consistency) within a situation, often treating within-situation variability as mere error. This study investigates three primary questions involving behavioral variability: (a) Is variability a general characteristic of individuals or contingent on situational factors? (b) Do situations influence behavioral variability either by allowing for more behavioral variability or by increasing behavioral consistency? (c) Do personality traits interact with situations to affect variability? Utilizing intensive longitudinal data from two studies, we developed a novel person-in-situ density distribution model to capture person-specific within-situation variability. Our findings indicate that behavioral variability is not solely a function of individual differences but also significantly shaped by situational contexts. Meanwhile, contrary to the strong situation hypothesis, which emphasizes that situations tend to constrain behaviors, the present study found situations influence behavioral variability in both directions, making people more and less variable. Finally, personality traits were found to moderate the impact of situations on behavioral consistency, suggesting that variability reflects the interplay between person and situation factors. These results highlight the importance of considering behavioral variability within situations, which offers insights into personality dynamics rather than exclusively focusing on mean-level analyses. The implications of the person-in-situ density distribution model for studying person-situation transactions are also discussed. (PsycInfo Database Record (c) 2025 APA, all rights reserved).