The average American knows about 600 people. How do we know this? Researchers led by my Columbia colleague Tian Zheng posed a series of questions to a representative sample of 1,500 Americans: How many people do you know named Kevin? How many named Karen? How many named Shawn or Sean, Brenda, Keith or Rachel?
After adjusting for various factors (for example, the names are not evenly distributed in age across the population), we determined that participants knew an average of 8.4 people with those names. Social Security records suggest that 1.4 percent of the population has one of the names, and 8.4 divided by 1.4 percent is 600 people.
Using this clever method of estimating social networks can be tricky. Indeed, the method's inventors, H. Russell Bernard and Peter Killworth, estimated from an earlier survey that the average American knew only 290 people.
Why was their estimate so low? Perhaps because the names they used were common ones, like Michael and Robert; research shows that people with common names are harder to recall than those with slightly more exotic ones, like Sean and Rachel.
Our team also estimates that most Americans know just 10 to 25 people well enough to say they trust them.science
This article originally appeared in The New York Times.