In prospect theory, loss aversion refers to the tendency for people strongly to prefer avoiding losses than acquiring gains. Some studies suggest that losses are as twice much psychologically powerful as gains. Loss aversion was first convincingly demonstrated by Amos Tversky and Daniel Kahneman. Image File history File links Unbalanced_scales. ... Shortcut: WP:NPOVD Articles that have been linked to this page are the subject of an NPOV dispute (NPOV stands for Neutral Point Of View; see below). ... Prospect theory was developed by Daniel Kahneman and Amos Tversky in 1979 as a psychologically realistic alternative to expected utility theory. ... Amos Tversky (March 16, 1937 - June 2, 1996) was a pioneer of cognitive science, a longtime collaborator of Daniel Kahneman, and a key figure in the discovery of systematic human cognitive bias and handling of risk. ... Daniel Kahneman Daniel Kahneman (born March 5, 1934 in Tel Aviv, in the then British Mandate of Palestine, now in Israel), is a key pioneer and theorist of behavioral finance, which integrates economics and cognitive science to explain seemingly irrational risk management behavior in human beings. ...

This leads to risk aversion when people evaluate a possible gain; since people prefer avoiding losses to making gains. This explains the curvilinear shape of the prospect theory utility graph in the positive domain. Conversely people strongly prefer risks that might possibly mitigate a loss (called risk seeking behavior). Risk aversion is a concept in economics and finance theory explaining the behaviour of consumers and investors under uncertainty. ... Prospect theory was developed by Daniel Kahneman and Amos Tversky in 1979 as a psychologically realistic alternative to expected utility theory. ... This article is about the concept of risk. ...

Loss aversion may also explain sunk cost effects. It has been suggested that Bygones principle be merged into this article or section. ...

Loss aversion implies that one who loses $100 will lose more satisfaction than another person will gain satisfaction from a $100 windfall. In marketing, the use of trial periods and rebates try to take advantage of the buyer's tendency to value the good more after he incorporates it in the status quo. For the magazine, see Marketing (magazine). ...

Note that whether a transaction is framed as a loss or as a gain is very important to this calculation: would you rather get a 5% discount, or avoid a 5% surcharge? The same change in price framed differently has a significant effect on consumer behavior. Though traditional economists consider this "endowment effect" and all other effects of loss aversion to be completely irrational, that is why it is so important to the fields of marketing and behavioral finance. The endowment effect is a hypothesis that people value a good (object) more once their property right to it has been established. ... Irrationality is talking or acting without regard of rationality. ... For the magazine, see Marketing (magazine). ... Economics Nobel Laureate Daniel Kahneman, was an important figure in the development of behavioral finance and economics and continues to write extensively in the field. ...

Can loss aversion ever be rational?

There is an important critique of the view held by economists that this behaviour is irrational. The implicit assumption of conventional economics is that the only relevant metric is the magnitude of the absolute change in expenditure. In the above example, saving 5% is considered equivalent to avoiding paying 5% extra. This is not the only rational interpretation. Another view is that the most important metric is the magnitude of the relative change in wealth of the decision-maker. Again, referring to the above example, a 5% discount is then not equivalent to avoiding a 5% surcharge. The reasoning is as follows. This article does not cite any references or sources. ...

Take a hypothetical item with a base cost of $1000, and consider two possible scenarios:

• In the first scenario, the buyer expects to pay $1000, but then is offered a 5% discount. The price is then $950. The change represents a 5% saving.
• In the second scenario, there is a surcharge of 5%, or $50. The buyer expects to pay $1050. Avoiding the surcharge would mean a price of $1000. Buyers see this as a savings of $50 on what they expected to pay: $1,050. Thus, the perceived savings is 50/1050 x 100% = approx. 4.76%.

When the savings relative to the remaining wealth (or stock of money) is different, the value of the transaction changes accordingly. When using this interpretation, decisions made by consumers are not necessarily irrational.

Taking this to an extreme, if a person has only $1000, getting $1000 simply doubles their wealth (which would be desirable), but losing $1000 would wipe them out completely (which might be a matter of life and death). In this case, given the need for money for food and shelter in order to survive, the individual will be far more motivated to avoid losing $1000 than to try to gain $1000.

In addition, it has been asserted that the effect of relative evaluation is more pronounced the greater the potential amount saved is relative to the total amount the decision-maker has to spend.

All of the above effects can be expressed in terms of the utility function of money, and, in particular, not regarding money as a linear measure of utility. In other words, if money has diminishing marginal utility, then each dollar is worth less than the one before it. To use the example before, the first $1000 might be worth $1000 to a person, and the second $1000 worth only $950 (in terms of utility). This would not be "loss aversion" but just a phenomenon adequately explained by economic theory. This article is about utility in economics and in game theory. ... In economics, marginal utility is the additional utility (satisfaction or benefit) that a consumer derives from an additional unit of a commodity or service. ...

Social Psychology

Loss aversion is a concept of Social Psychology as much as economics. It is not the reality of loss that matters but the perception. This is one place where being good at math doesn't give the answer. Nations have gone to war and "stayed the course" until their doom because of loss aversion. It simply means you refuse to admit you made a mistake. Social Psychology Fourth Edition, Aronson et al., p. 175: "Once we have committed a lot of time or energy to a cause, it is nearly impossible to convince us that it is unworthy" The real question is "How bad do your losses have to be before you change course?" In stocks this is called capitulation. The term Cognitive Dissonance will lead to further explanation of this effect. Cognitive dissonance is a psychological term which describes the uncomfortable tension that may result from having two conflicting thoughts at the same time, or from engaging in behavior that conflicts with ones beliefs. ...

An Alternative Example

Imagine that your country is preparing for an outbreak of a disease which is expected to kill 600 people. Given the choice between two vaccination schedules, Program A which will save 200 and Program B which will save all 600 with probability 1/3, most will choose Program A.^[1]

However, if the question is framed as:

Imagine that your country is preparing for an outbreak of a disease which is expected to kill 600 people. Given the choice between two vaccination schedules, Program C which will allow 400 people to die and Program D which will let no one die with probability 1/3 and all 600 will die with probability 2/3, most people will choose option D.

This is an example of loss aversion: the two situations are identical in quantitative terms, but in the second one the decision maker is losing instead of saving lives, thus setting 0 lives lost as the status quo from which losses are measured, making the sure loss of 400 people more loathsome than the probable loss of 600.

See also

• Risk aversion
• Status quo bias
• List of cognitive biases

Risk aversion is a concept in economics and finance theory explaining the behaviour of consumers and investors under uncertainty. ... Status quo bias is cognitive bias for the status quo; in other words, people like things to stay relatively the same. ... Cognitive bias is distortion in the way humans perceive reality (see also cognitive distortion). ...

References and links

• Hickman, J. (2003). "Bush in Baghdad". Baltimore Chronicle.
• Kahneman, D. & Tversky, A. (1979). Prospect Theory: An Analysis of Decision under Risk. Econometrica 47, 263-291.
• Tversky, A. & Kahneman, D. (1991). Loss Aversion in Riskless Choice: A Reference Dependent Model. Quarterly Journal of Economics 106, 1039-1061.
• "A Psychological Law of Inertia and the Illusion of Loss Aversion", David Gal, September 2005
• "Loss Aversion, Risk, & Framing: The Psychology of an Influence Strategy", Kelton Rhoads, 1997.

References