What do you learn about someone over time? The relationship between length of acquaintance and consensus and self-other agreement in judgments of personality.

Theory and research examining length of acquaintance and consensus among personality judgments have predominantly examined each dimension of personality separately. In L. J. Cronbach's (1955) terminology, this trait-centered approach combines consensus on elevation, differential elevation, and differential accuracy in personality judgments. The current article extends D. A. Kenny's (1991, 1994) weighted average model (WAM)--a theoretical model of the factors that influence agreement among personality judgments--to separate out two of Cronbach's components of consensus: stereotype accuracy and differential accuracy. Consistent with the predictions based on the WAM, as length of acquaintance increased, self-other agreement and consensus differential accuracy increased, stereotype accuracy decreased, and trait-level or raw profile correlations generally remained unchanged. Discussion focuses on the conditions under which a relationship between length of acquaintance and consensus and self-other agreement among personality evaluations emerges and how impressions change over time.