Validity of observer ratings of the big five personality factors.

Examined the validity of observer (supervisor, coworker, and customer) ratings and self-ratings of personality measures. Results based on a sample of 105 sales representatives supported the 2 hypotheses tested. First, supervisor, coworker, and customer ratings of the 2 job-relevant personality dimensions—conscientiousness and extraversion—were valid predictors of performance ratings, and the magnitude of the validities was at least as large as for self-ratings. Second, supervisor, coworker, and customer ratings accounted for significant variance in the criterion measure beyond self-ratings alone for the relevant dimensions. Overall, the results suggest that validities of personality measures based on self-assessments alone may underestimate the true validity of personality constructs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)