<p>This isn’t necessarily just a “superstar” thing, it’s a self-confidence thing. </p>
<p>There was a similar study made with race: a group of African-American students performed worse on average when proctored by a white male and led to perceive the test as racially biased than when proctored by a black male and led to perceive the test as unbiased, on the same test.</p>
<p>If you walk into that test room convinced you WILL perform exactly as you expect on a practice test, you probably will.</p>