Meaning
Loss aversion is a behavioral bias described in prospect theory. It states that the displeasure from a loss is typically stronger than the pleasure from an equivalent gain, making losses more psychologically impactful than gains.
In behavioral finance, loss aversion helps explain why people react differently to risk than traditional models assume. The bias can influence decision making under uncertainty, including how information is framed (loss frames vs. gain frames) and how much weight is given to downside scenarios. People may require larger potential gains to accept a risky option than they require to avoid a similar-sized loss, which can lead to risk-averse choices in the short term and a preference for avoiding irreversible losses in the long run. It can also contribute to status quo bias, the tendency to stick with a current portfolio rather than accept a risk to improve returns.
In portfolio thinking, loss aversion can affect perceptions of drawdowns, risk tolerance, and the framing of information presented to investors. It interacts with other behavioral concepts such as the endowment effect and framing effects, shaping how people evaluate gains and losses over time.
Example: In a study, respondents reacted more strongly to a potential $1,000 loss than to a $1,000 gain.
Prospect Theory · Risk Aversion · Endowment Effect · Framing Effect · Mental Accounting · Disposition Effect