A recent study has indicated that people instinctively know how accurate their first impressions are.
According to it people know when their first impressions are correct reasonably well.
Researchers had two separate groups of more than 100 people meet in a "getting-acquainted" session much like speed-dating, until the people had spoken with everyone else in the group for three minutes each. At the end of each 3-minute chat, they rated each other's personalities, and rated how well they thought their impressions "would agree with someone who knows this person very well." To establish what the person was "really" like, the researchers had people fill out their own personality reports, which were bolstered with personality ratings that came either from friends or parents.
There is a large body of research that shows impressions can be accurate with short interactions, and the participants did a reasonably good job of seeing each other's personality. And the more accurate they felt, the closer their ratings were to the ratings coming from their friends and parents.
The participants also found the highest accuracy from people who rated themselves moderately accurate-when people were highly confident of their judgment, accuracy was not greater than for moderate levels of confidence.
Jeremy Biesanz of the University of British Columbia, who led the research team, noted "Although our first impressions are generally accurate, it is it critical for us to recognize when they may be lacking". The study has been published in the Social Psychological and Personality Science.