The Economist highlighted research from the recent issue of the Journal of Economic Perspectives about the “social connectedness” of Americans. The paper by Michael Bailey, Rachel Cao, Theresa Kuchler, Johannes Stroebel, and Arlene Wong created a “Social Connectedness Index” based on friendship links on Facebook, providing the first comprehensive measure of friendship networks on a national level. They found that Americans with tightly clustered social networks within a short distance of their home tended to have lower incomes, education, and life expectancies than people with more far-flung networks.