Americans Are Bad at Guessing the Size of Demographic Groups
Two new surveys from YouGov show Americans rarely estimate the size of demographic groups correctly, and tend to vastly overestimate the size of smaller ones.
Respondents were asked to guess the percentage (from 0% to 100%) of U.S. adults who are members of 43 different groups, revealing a pattern of Americans’ average perceptions of the size of minority groups being much larger than the groups actually are.
The pattern held true across all minority groups in the survey. Below are some highlights.
Muslim Americans (estimate: 27%, true: 1%)
Jewish Americans (estimate: 30%, true: 2%)
Black Americans (estimate: 41%, true: 12%)
Asian Americans (estimate: 29%, true: 6%)
Native Americans (estimate: 27%, true: 1%)
Gay and lesbian adults (estimate: 30%, true: 3%)
Bisexual adults (estimate: 29%, true: 4%)
Transgender adults (estimate: 21%, true: 0.6%)
Left-handed adults (estimate: 34%, true: 11%)
Household income above $500,000 (estimate: 26%, true: 1%)
Vegan or vegetarian adults (estimate: 30%, true: 5%)
Union members (estimate: 36%, true: 4%)
A parallel pattern of people underestimating the size of majority groups also emerged:
Christian Americans (estimate: 58%, true: 70%)
Have a high school degree (estimate: 65%, true: 89%)
Household income under $25,000 (estimate: 62%, true: 82%)
Have flown on a plane (estimate: 59%, true: 88%)
What’s behind it?
Without getting into the weeds, YouGov says the findings stem from people’s tendency to rescale their perceptions in a rational way, accounting for their own biases and attempting to correct their estimates accordingly.
This reasoning process, called uncertainty-based rescaling, leads people to systematically overestimate the size of small values and underestimate the size of large ones, according to YouGov.