You Win

We may be overly optimistic when predicting others’ success.

By Kieran McLean, published October 10, 2019 - last reviewed on November 5, 2019


Forecasting the future is always tricky, and trying to predict our own can spur doubt, second-guessing, and pessimism. But recent research from the Journal of Personality and Social Psychology suggests that when we predict what outcomes others might achieve, our views may be overly positive—because we largely only consider the possibility that they’ll succeed.

Across eight experiments, researchers asked participants to evaluate another’s chances of success in photography, golf, or marketing competitions. They found that because people only “test” the likelihood of one hypothesis when they predict the future—and because their first hypothesis is usually that the other person will succeed—they tend to significantly overestimate their  target’s chance of success. This effect held even when the contests were known to be highly competitive and there was little chance their favorite would actually be the victor.  

Further, when researchers explicitly asked them to consider the possibility that the target might lose the contest, participants were more likely than before to predict that person’s failure. “Observers spontaneously test the hypothesis that their [preferred] outcome will occur, which biases them to overestimate the likelihood that it will,” says lead author Daniella Kupor of Boston University.