Availability heuristic

The availability heuristic is a mental shortcut that relies on immediate examples that come to a given person's mind when evaluating a specific topic, concept, method or decision. The availability heuristic operates on the notion that if something can be recalled, it must be important, or at least more important than alternative solutions which are not as readily recalled. Subsequently, under the availability heuristic, people tend to heavily weigh their judgments toward more recent information, making new opinions biased toward that latest news.

The availability of consequences associated with an action is positively related to perceptions of the magnitude of the consequences of that action. In other words, the easier it is to recall the consequences of something the greater those consequences are often perceived to be. Most notably, people often rely on the content of their recall if its implications are not called into question by the difficulty that they experience in bringing the relevant material to mind.

Prior to the work of Kahneman and Tversky, the predominant view in the field of human judgment was that humans are rational actors. However, in the late 1960s and early 1970s Amos Tversky and Daniel Kahneman began work on a series of papers examining "heuristic and biases" used in judgment under uncertainty. They explained that judgment under uncertainty often relies on a limited number of simplifying heuristics rather than extensive algorithmic processing. Soon this idea spread beyond academic psychology, into law, medicine, and political science. This research questioned the descriptive adequacy of idealized models of judgment, and offered insights into the cognitive processes that explained human error without invoking motivated irrationality. One simplifying strategy people may rely on is the tendency to make a judgment about the frequency of an event based on how many similar instances are brought to mind. In 1973, Amos Tversky and Daniel Kahneman first studied this phenomenon and labeled it the "availability heuristic". An availability heuristic is a mental shortcut that relies on immediate examples that come to a given person's mind when evaluating a specific topic, concept, method or decision. As follows, people tend to use a readily available facet to base their beliefs about a comparably distant concept.There has been much research done with this heuristic, but studies on the issue are still questionable with regard to the underlying process. Studies illustrate that manipulations intended to increase the subjective experience of ease of recall are also likely to affect the amount of recall. Furthermore, this makes it difficult to determine if the obtained estimates of frequency, likelihood, or typicality are based on participants phenomenal experiences or on a biased sample of recalled information.

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