People tend to underestimate how wealthy the richest individuals are, according to a recent study. While income inequality has been growing in many countries, driven by steep gains among the top 1%, support for policies to redistribute wealth has remained stagnant. In the U.S., despite the fact that the top 1% now control nearly 19% of total income—up from 10% in the 1970s—public opinion on wealth redistribution hasn’t shifted.

Researchers conducted four studies to explore how well people grasp the wealth held by others. In one study, 990 U.S. residents were asked to estimate the minimum annual household income needed to be in various income percentiles. Participants tended to underestimate the income of the top 1%, while their guesses for lower percentiles were more accurate. The findings were confirmed in a second survey of 834 U.S. participants, who were incentivized to guess accurately with the promise of cash rewards.

Underestimating income

In two additional experiments, participants were shown images and income data for members of a fictional society, allowing the researchers to manipulate how wealth was distributed. Here again, participants underestimated the income of the top 20%, though they were more precise in guessing the incomes of lower groups.

The researchers suggest that this underestimation may be due to “scope insensitivity”—a cognitive bias where people struggle to grasp large differences in scale. For example, the idea of a billionaire making another million doesn’t have the same impact as imagining someone earning $50,000 suddenly making a million. This broad sense of “rich” replaces the finer details of wealth distribution in people’s minds, leading to a distorted understanding of just how wealthy the very rich are.