This research suggests that when you ask someone to rate the personality of a particular coworker or acquaintance, you may learn as much about the rater providing the personality description as the person they are describing. The level of negativity the rater uses in describing the other person may indeed indicate that the other person has negative characteristics, but may also be a tip off that the rater is unhappy, disagreeable, neurotic-or has other negative personality traits.
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My-Pedia 