In tight-knit counties, fewer people move in or out

Some places are tight-knit: your friends are friends with each other. Others are loose, with friendships that do not overlap much. Across US counties, the tight-knit ones have less coming and going. Fewer people leave, and fewer people arrive. That holds after every check we could throw at it.

How tight-knit a county is

The measure is the mutual-friend share: of all the friendships between two people in a county, the share where the two also have a friend in common nearby. It comes from Facebook friendships in 2022, made private and published by Opportunity Insights. Moving comes from IRS tax returns: how many filers moved out or moved in in a year, for every 100 who stayed.

Fewer people leave

Each dot is a county. Across 3,067 counties, the more tight-knit a county, the fewer people leave it: −0.48.

The chart leaves off the 83 most extreme counties so the rest can be seen. Every figure on this page uses all of them.

Every figure here is r: how closely two measures rise and fall together, from −1 (one goes up as the other goes down) to +1 (they rise together). 0 means no link.

It is not about cities, money, age or poverty

Big cities have loose networks and a lot of moving, so the first check compares counties alike in how crowded, rich and educated they are. The link stays at −0.48. Comparing counties only with others in their own state: −0.45. Older counties might be both settled and close-knit, but allowing for age leaves −0.45. Allowing too for poverty, homeownership and the share born abroad leaves −0.56, across the 2,399 counties with all of these figures.

Giving bigger counties more weight, so the figure describes the average resident rather than the average county, gives −0.44. Inside the 40 states with at least 20 counties, the link runs the same way in 39, with a middle value of −0.52.

Fewer people arrive, too

The same is true of people moving in: −0.44 after comparing counties alike in density, income and education, and −0.42 after the other checks. It runs the same way in 40 of 40 states.

What it might mean

The link could run either way, or both. Close networks may give people reasons to stay, such as family nearby, help with childcare and a job found through a friend. Or places where few people move have more time to build overlapping friendships, since newcomers start with friends who do not know each other. The data shows the two go together. It cannot say which comes first.

What this cannot tell you

• It describes counties, not people. It does not show that people with close friends move less.
• Friendships are measured on Facebook, which not everyone uses in the same way.
• Tax returns miss people who do not file, and the moves are counted as filers, not individuals.
• A link is not proof that one thing changes the other.

See the full figures for mutual-friend share vs people leaving and vs people arriving.

More articles

• Countries where people have a say collect more tax
• The puzzle of women managers and homicide
• Where more women work, people drink more
• Friendships across income lines, and how far poor children climb
• US Murder (Homicide) Rate: What Drives It?
• Where the rich move

These articles describe places, not people, and show links, not causes. Every article on PlaceStats.