Is Loss Aversion a Myth?

The idea of loss aversion – that losses ‘loom’ larger than gains – is one of the most established and prominent findings in behavioural economics, and could be considered a foundation stone for the entire discipline.  Recent research, however, has questioned the validity and robustness of the supporting evidence, suggesting that it is at worse a false concept and at best overstated (in particular see Yechiam 2018, Gal & Rucker 2017).  Given the issues surrounding p-hacking and failed replications, placing such widely-accepted beliefs under scrutiny should be applauded yet, in this instance, some of the claims appear exaggerated.

One prominent criticism of loss aversion has been that its presence is reliant on the stakes involved being of a sufficient magnitude –  the evidence evaporates if the potential loss or gain is not meaningful.  Harinck et al. (2007) argue that the loss aversion phenomenon actually reverses when the amounts of money involved in a decision are small.  This makes intuitive sense – if an individual were gambling a minor amount of ‘play money’ on a slot machine during a visit to a casino, they are unlikely to be particularly loss averse, indeed the ‘utility’ from winning could easily outstrip any pain from losing.  Conversely, if a risky decision has the potential to incur a material cost, then the classical features of loss aversion should take hold.

The extent to which a loss is considered meaningful or an amount of money considered ‘small’ will also be heavily dependent on its size relative to wealth.  The same monetary amount at stake could be viewed as inconsequential to an affluent individual, yet incredibly valuable to another with less resources – the ‘marginal utility’ of the lost money would be far greater in the latter instance.

The influence of bet size and relative materiality are two reasons why it is difficult to create general rules around the concept of loss aversion; however, more vital, and certainly less prominent, is the importance of reference points.  Reference points dictate what is considered a loss or gain – we can think of them as a break even point. Although in certain circumstances defining a loss may seem simple, this is far from the case – losses are subjective rather than objective. Understanding reference points is crucial in ascertaining how and where loss aversion may occur.

The major problem is that reference points are not fixed, but subject to a multitude of behavioural biases and heavily dependent on individual differences, environment and decision context.  Let’s take a simple investment example to illustrate the point:

There are three investors, A, B and C, each have been invested in the same portfolio for the previous 12 months.  Over this period, the portfolio has fallen in value 10% and its benchmark has lost 15%.  From the perspective of loss aversion and reference points, how does each investor feel about this outcome?

– Investor A is satisfied with the performance relative to the benchmark and considers it to be a ‘gain’.

– Investor B is disappointed with the absolute loss suffered by the portfolio over the period.

– Investor C is pleased with the returns as he just spoke with his friend and their portfolio lost 22% over the same period.

This is a heavily stylised example, but aims to emphasise the point that reference points can vary between individuals and within individuals, and in many cases it is impossible to know what that reference point is.  Absent that information, it becomes difficult to precisely understand or predict behaviour consistent with loss aversion in all situations.  Of course, in certain circumstances the reference point might be obvious or we might be able to decipher it from analysing individual behaviour, but they should still be considered highly variable and vulnerable to manipulation.

Given that the genesis of behavioural economics was, at least in part, a reaction to the rigidity of classical economics and the ultra-rational assumptions made about individual / collective behaviour, it seems nonsensical to criticise loss aversion for not being universally applicable.  It is, however, useful to be reminded that circumspection is required when making broad claims about any research findings.

Will loss aversion appear in a consistent fashion, irrespective of context or individual difference?  No, but in some ways that it the point.

Key Reading:

Gal, D., & Rucker, D. (2017). The Loss of Loss Aversion: Will It Loom Larger Than Its Gain?.

Harinck, F., Van Dijk, E., Van Beest, I., & Mersmann, P. (2007). When gains loom larger than losses: Reversed loss aversion for small amounts of money. Psychological science18(12), 1099-1105.

Yechiam, E. (2018). Acceptable losses: the debatable origins of loss aversion. Psychological research, 1-13.

Please note all views expressed in this article are my own and are not necessarily shared by my employer.

2 thoughts on “Is Loss Aversion a Myth?

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