Cognitive Bias - Overview

Overview

Bias arises from various processes that are sometimes difficult to distinguish. These include information-processing shortcuts (heuristics), mental noise and the mind's limited information processing capacity, emotional and moral motivations, or social influence.

The notion of cognitive biases was introduced by Amos Tversky and Daniel Kahneman in 1972 and grew out of their experience of people's innumeracy, or inability to reason intuitively with the greater orders of magnitude. They and their colleagues demonstrated several replicable ways in which human judgments and decisions differ from rational choice theory. They explained these differences in terms of heuristics, rules which are simple for the brain to compute but introduce systematic errors. For instance the Availability heuristic, when the ease with which something comes to mind is used to indicate how often (or how recently) it has been encountered.

These experiments grew into the heuristics and biases research program which spread beyond academic psychology into other disciplines including medicine and political science. It was a major factor in the emergence of behavioral economics, earning Kahneman a Nobel Prize in 2002. Tversky and Kahneman developed prospect theory as a more realistic alternative to rational choice theory.

Critics of Kahneman and Tversky such as Gerd Gigerenzer argue that heuristics should not lead us to conceive of human thinking as riddled with irrational cognitive biases, but rather to conceive rationality as an adaptive tool that is not identical to the rules of formal logic or the probability calculus.