8.6: Hindsight Bias

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When we learn some fact or the outcome of some event, we have a strong tendency to think that we would have predicted it beforehand. This “I knew it all along” syndrome is called hindsight bias. Hindsight bias has been found in elections, medical diagnoses, sporting events, and many other settings. A consequence of this phenomena is it confirms a base belief that we almost all have that we are right (“I knew that would happen”) more often than we really are. This makes it more difficult to correct our mistakes by learning from past errors, since we don’t even notice them. As a result, people who find themselves falling victim to hindsight bias frequently are less likely to be fallible about any of their beliefs.

Remedies

Warning people of the dangers of hindsight bias has little effect. But we can reduce it by considering how past events might have turned out differently. Ask yourself what alternatives might have occurred, and what factors would have made it likely that they would have happened. Additionally, if you are making a prediction that is genuinely important to you, a written record can work as a real safeguard.