Neglect of Probability

The neglect of probability, or probability neglect, is a cognitive bias describing the tendency to disregard probability entirely when making a decision under uncertainty, one of the simple ways in which people regularly violate the normative rules of rational decision-making. A small risk is typically either ignored altogether or wildly overrated, with little sensitivity to the actual continuum of probability in between, and the legal scholar Cass Sunstein coined the term probability neglect. It is related to several other violations of normative decision-making already live on this atlas, including hindsight bias, base rate fallacy and the gambler's fallacy, though those involve incorrectly using probability rather than disregarding it outright; as the author Rolf Dobelli has put it, people have no intuitive grasp of risk, so a reduction in risk affecting a serious, emotionally charged threat feels far less reassuring than the numbers alone would justify.