The First Instinct Fallacy

Panicked test-takers are often advised to go with their first impulse when answering tough questions on multiple-choice exams such as the SAT.

But a study has found that this strategy may actually hurt performance. That's because, on average, test takers most often change answers from incorrect to correct, improving their test scores.

This "first instinct fallacy" persists, says Justin Kruger, a psychologist at the University of Illinois at Urbana-Champaign, because instances when we change an answer from right to wrong loom larger in memory and lead to frustrated "if only" self-recriminations. Changing an answer from wrong to right is not as memorable, creating the illusion that it happens less often.