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highlighted research from the recent issue of the Journal of Economic Perspectives about the “social connectedness” of Americans. The paper by , , , , and created a “Social Connectedness Index” based on friendship links on , 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.