Abstract
Group polarization is defined as a tendency for average post‐discussion positions to be in the direction of, but more extreme than, prediscussion positions. One explanation for this phenomenon is that, during interaction, group members increasingly value their prediscussion individual decisions because of the communication of persuasive arguments supporting these positions. Previous research has shown that group members who have similar attitudes about a discussion topic or who discuss an issue that is relevant will communicate persuasive arguments and polarize in their decision‐making. The present study, however, focuses on personality as a predispositional factor which is predictive of the direction of both persuasive argumentation by group members and, subsequently, decisional shifting. Findings tend to validate the value theory of polarization by showing that persuasive argumentation can mediate the effect of personality on decisional shifting.