Pessimism bias is an effect in which people exaggerate the likelihood that negative things will happen to them. It contrasts with optimism bias

Optimism bias

Optimism bias is the demonstrated systematic tendency for people to be overly optimistic about the outcome of planned actions. This includes over-estimating the likelihood of positive events and under-estimating the likelihood of negative events. Along with the illusion of control and illusory...

, 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

Heart disease

Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...

showed a small but significant pessimism bias.