City life is often described as “fast-paced.” A study coauthored by MIT scholars suggests that’s more true than ever: The average walking speed in three northeastern US cities increased 15% from 1980 to 2010, while the number of people lingering in public spaces declined by 14%.

The researchers used machine-learning tools to assess 1980s-era video footage captured in Boston, New York, and Philadelphia by William Whyte, an urbanist and social thinker best known as the author of The Organization Man. They compared the old material with newer videos from the same locations.

“Something has changed over the past 40 years,” says coauthor Carlo Ratti, director of MIT’s Senseable City Lab. “Public spaces are working in somewhat different ways, more as a thoroughfare and less a space of encounter.” The scholars speculate that some of the reasons may have to do with cell phones and Starbucks: People text each other to meet up instead of hanging around to encounter each other in public, and when they do get together, they often choose an indoor space like a coffee shop.

The results could help designers seeking to create new public areas or modify existing ones. “Public space is such an important element of civic life, and today partly because it counteracts the polarization of digital space,” says Arianna Salazar-Miranda, MCP ’16, PhD ’23, an assistant professor at Yale and another coauthor. “The more we can keep improving public space, the more we can make our cities suited for convening.”