How to solve a problem like confirmation bias

You can hear Eva, one of your colleagues, before you see her. She’s going round the office jauntily shaking a collection tin. Eva’s drumming up sponsors for a marathon she’s running. Your colleagues are impressed by her altruism. But you’re not fooled, not for a second. It’s an obvious ploy to win popularity.

You’re displaying signs of confirmation bias. Because Eva was promoted ahead of you, you’re cynical about her motivations, interpreting them through a lens of your existing feelings.

The evidence for confirmation bias stretches back to the experiments of Albert Hastorf and Hadley Cantril. The psychologists based their findings on an American football game between stark rivals: Princeton and Dartmouth University. In the psychologists’ turn of phrase, the game was full of “rough play”.