The NYT has a fantastic new bit of data visualization: “How Connected Is Your Community to Everywhere Else in America?” The piece uses data from Facebook ties to show how geography shapes our ties. The overwhelming pattern is that counties are tied to adjacent counties. As the article reminds us, “The typical American lives just 18 miles from his or her mother. The typical student enrolls in college less than 15 miles from home.” Other, subtler, patterns are interesting too. As an example, below are charts for three counties in southeast Michigan: Washtenaw (which include the University of Michigan, Ann Arbor), Oakland (a rich county of Detroit suburbs) and Wayne (which includes Detroit itself).
You can clearly see in the Washtenaw County map connections to other college towns. These connections are especially stark in contrast with Oakland, which has almost no East or West Coast ties:
In contrast, what jumps out from comparing Oakland to Wayne is Wayne’s strong ties to the Deep South, likely a legacy of the Great Migration of Black Southerners to industrial cities in the North (a common trend, as the NYT piece notes):
The article ends with a quote from none other than Mark Granovetter:
“This gives us the first way to systematically look at some of those relationships,” said Mark Granovetter, a sociologist at Stanford who has written influential papers on the value of social networks. “They have just scratched the surface here.”
What do you see?
scatterplot 
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