Reducing loss aversion and regret in investing


Behavioural economists and psychologists have tried to explain why stock market participation is low among households despite their historically higher average returns compared to other forms of investing. They have shown it’s because of our aversion to losses. The past few weeks has provided an example why people shun share markets but we think this will be overcome.

Since the 18th century economic theory was built on the foundation that humans assessed losses and gains equally. It has only been in the last 50 years or so that behavioural economists and psychologists have proven this is not the case.

This fundamental flaw in economic theory has been exposed because:

  1. the old theory fails to allow for different reference points;
  2. humans are more sensitive to reductions in wealth than increases; and
  3. feelings such as regret were not considered.

Behavioural economist Richard Thaler and psychologist Daniel Kahneman have both been awarded Nobel prizes for their research into the behaviour and decision making processes of humans and the role of these processes in understanding the broader field of economics. Understanding their findings about reference points, loss aversion and regret can help the investment industry counsel their clients through the most turbulent market in history.

Importance of a reference point

To highlight the importance of a reference point Kahneman, in Thinking, Fast and Slow, uses the following example. He uses the monikers Anthony and Betty.

Anthony currently has $1 million, Betty $4 million. They are both offered a choice between a gamble and sure thing. The gamble would leave them with either $1 million or $4 million. Doing nothing and accepting the sure thing is to own $2 million. The theories that underpin most economic principles assume Anthony and Betty will make the same choice because the theory does not consider the reference points that Anthony and Betty will consider when making their judgements.

Anthony who currently has $1 million will double his wealth with the sure thing. This is attractive. Alternatively, he can gamble with equal chances to quadruple his wealth or gain nothing. That’s risky. Betty, on the other hand, will almost certainly baulk at the certain $2 million outcome because that means she will lose half her wealth. Alternatively, she can gamble and lose three quarters or retain her $4 million. You can see that Anthony and Betty are going to make different choices.

The reference points, make the ‘sure’ outcome good for Anthony and bad for Betty.

You’ll note, Betty, faced with a loss becomes a risk seeker. This underpins Prospect Theory, people seek risk when all the options are bad. It sounds counterintuitive but it’s true.

Prospect Theory or the human response to losses is stronger than to gains

Consider these two problems (again, these are summarised from Thinking, Fast and Slow)

1 – You have been given $1,000?
You are now asked to choose one of these options:
50% chance to win $1,000 OR get $500 for sure


2 – You have been given $2,000?
You are now asked to choose one of these options:
50% chance to lose $1,000 OR lose $500 for sure

The ‘sure’ outcome to both problems is $1,500. Most people are risk averse in problem 1 and accept the sure $500. However in problem two, they are more likely to gamble, even though the probability is high that they will lose $1,000 not $500.

What researchers discovered was that, when weighed against each other, losses loom larger than gains and humans will do all they can to avoid losses. This a principle of Prospect Theory. According to Kahneman this process has an evolutionary history, “Organisms that treat threats as more urgent than opportunities have a better chance to survive and reproduce.” This might have helped us in the wild, but its results in the investment world vary. Investors must evaluate and assess start-ups, company results and future prospects each with uncertain outcomes.

The options investors face every day involve a risk of loss and an opportunity for gain. We generally do not like to accept the risk of losses For example, Behartzi and Thaler (1995), pondered why individual investors continued to shun stocks even though their real returns had been about 7% per year since 1926. They attempted to determine what ‘premium’ people would accept to consider this higher returning option, which could incur short-term periods of losses. Behartzi and Thaler found individual investors were “unwilling to accept return variability even if the short-run returns have no effect on immediate consumption.”

Behartzi and Thaler made reference to ‘organisations’, to test if they too were loss averse. They found pension and endowment funds were also susceptible to loss aversion, but that they were however were more likely to have significant exposure to growth assets given the long term nature of their investment objectives.

Of course, back in 1995 when Behartzi and Thaler wrote their paper, many people were not yet exposed to long term investing for pensions. The superannuation guarantee had only been introduced in Australia three years prior. Since then share ownership has increased. Australian investors, via their superannuation which is restricted from immediate consumption, have become more comfortable with the volatility that comes with stock market investing.

Given this increased level of comfort to save for the long term in their super, we wonder if Behartzi and Thaler did their research today in Australia, would they find a change in the level of risk aversion?

What Behatzi and Thaler’s models, as well as Prospect Theory, fail to allow is disappointment and regret.

That feeling of regret

Regret has been defined as “the pain we feel when we realise that we would be better off today if we had taken a different action in the past.” When you are investing you are exposed to possible future regret and people take this into consideration when they decide to allocate their money to an investment. This can lead to a process that behavioural economists call ‘narrow framing’. Barberis, Huang and Thaler (2006) found that narrow framing is a more important feature on decision making than previously realised especially when the outcome could lead to regret. Narrow framing is the process of using information that most accessible. For example, it is natural in the current market environment, to consider short-term returns. Unfortunately losses occur more often in risky assets when short term returns are considered, and for investors allocating to these risky asset classes this could lead to potential regret should losses occur and the gamble turns out poorly.

Alternatively, the regret could be missing out on gains.

This is where information filtering is paramount. Daily exposure to newspapers, books and online media with information about stock markets and bonds is accessible to everyone. In Australia, all working Australians are investors through the superannuation guarantee and their superannuation funds. We think over time this will continue to lead to superior decision making and active participation in markets by all Australians.

It’s important to look past the positive and negative commentary and concentrate on long term goals. Successful long-term investors survive short-term falls by sticking to investment principles that have withstood the tests of time. For portfolios, this may include better diversification. For equities, investing in profitable companies with strong balance sheets and stable earnings has historically given resilience to portfolios.

It’s interesting to note, in Thinking, Fast and Slow, when participants in Kahneman’s experiments are “instructed to ‘think like a trader,’ they become less loss averse and their emotional reaction to losses (measured by physiological index of emotional arousal) was sharply reduced.”



Barberis, Nicholas; Heung, Ming; Thaler, Richard H. (2006). "Individual preferences, monetary gambles, and stock market participation: a case for narrow framing". American Economic Review96 (4): 1069–1090

Benartzi, Shlomo; Thaler, Richard (1995). "Myopic loss aversion and the Equity Premium Puzzle". The Quarterly Journal of Economics110 (1): 453–458

Kahneman, D. (2011) Thinking, Fast and Slow, United States, Farrar, Straus and Giroux


Published: 03 April 2020