Chapter 5: Personality Judgment

Classic research by Rosenthal and Jacobson illustrates this phenomenon in educational settings, showing that teacher expectations directly shape student performance outcomes. The chapter then addresses the fundamental question of accuracy in personality judgment by introducing two primary evaluation criteria: interjudge agreement, where consensus among multiple judges suggests accuracy, and behavioral prediction, where accurate personality assessments demonstrate their validity through successful forecasting of future actions. The Realistic Accuracy Model provides a comprehensive framework explaining that accurate personality judgments require four necessary conditions working in conjunction. The relevant behavior must actually exist in the target person's behavioral repertoire, the behavior must be observable rather than hidden, the judge must actively detect and notice the behavior during social interaction, and the judge must correctly interpret what the observed behavior reveals about the underlying trait. The chapter identifies multiple moderating factors that influence judgment accuracy across different contexts. Individual differences matter substantially—some people function as good judges because of their elevated social intelligence and perceptiveness, while others as good targets display consistent and transparent behavior patterns that facilitate accurate assessment. The personality traits themselves vary in observability, with extraverted characteristics being more readily apparent than introverted or neurotic tendencies. The quality and quantity of available information also moderates accuracy, as extended interaction provides richer behavioral data. Importantly, the chapter challenges the intuitive assumption that people possess superior self-knowledge, presenting evidence that acquaintances sometimes assess behavioral patterns more accurately than the individuals themselves. The discussion of self-knowledge improvement emphasizes introspection, soliciting feedback from others, and developing the capacity to observe one's own behavior from an outside perspective as pathways toward enhanced self-understanding.