Pessimism bias

Pessimism bias is an effect in which people exaggerate the likelihood that negative things will happen to them. It contrasts with optimism bias, which is a more general, systematic tendency to underestimate personal risks and overestimate the likelihood of positive life events. Depressed people are particularly likely to exhibit a pessimism bias. Surveys of smokers have found that their ratings of their risk of heart disease showed a small but significant pessimism bias.