Research: Transit Times Determine Social Networks

A social network analysis, touted as the largest ever, reveals the importance of mobility for social connections.

1 minute read

July 16, 2019, 9:00 AM PDT

By James Brasuell @CasualBrasuell


New York Subway

littlenySTOCK / Shutterstock

"How do people meet, and maintain ties, in the big city?"

According to new research shared by Henry Grabar, in New York City, the main factor determining the answer to that question is transit time—which depends on transit lines.

"Call it the 'Take the ‘A’ Train' theory of socializing, after the Billy Strayhorn tune about the subway line that links Harlem and Bed-Stuy," writes Grabar.

The findings are from a working paper posted this month with the National Bureau of Economic Research, and led by Michael Bailey. The researchers claim they "have assembled the most comprehensive portrait to date of a city’s social network," reports Grabar.

Here, Grabar summarizes the findings of the study: "A 10 percent greater distance between two ZIP codes was associated with a decline in social connectedness of 8.7 percent. A 10 percent greater increase in cab cost was associated with a 10.6 decline in social connectedness. And a 10 percent greater public transit time is associated with 14.2 percent lower social connectedness."

Friday, July 12, 2019 in Slate

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