By behavioural psychologists Daniel Kahneman and Amos Tversky in 1973. In their classic experiment, they asked people to listen to a list of names and then recall whether there were more men or women on the list. Some people in the experiment were read a list of famous men and less famous women, while others were read the opposite. Afterwards, when quizzed by the researchers, individuals were more likely to say that there were more of the gender from the group with more famous names. Later researchers have linked this effect to how easily people could retrieve information: we tend to over-rely on what we can remember easily when coming to decisions or judgements.
Why does this matter? There’s solid evidence that experiencing such losses—noticing that our portfolio is losing money—leads to poor choices. In one lab experiment by Richard Thaler, Amos Tversky, Daniel Kahneman, and Alan Schwartz, subjects were far more likely to invest in a bond fund when feedback was given more frequently. Unfortunately, these low-risk bonds also generate lower returns over the long haul. As the scientists noted, “Providing such investors with frequent feedback about their outcomes is likely to encourage their worst tendencies…. More is not always better. The subjects with the most data did the worst in terms of money earned.” Such is the vicious circle of loss aversion, as our strong dislike of losses causes us to lose even more.