An intriguing new study argues that social interactions actually diminish in higher density settings. (Media coverage here, full pdf of study here.) What’s odd about this finding is that it’s in marked contrast to most other empircal studies of the relationship between density and social capital.
The literature on the subject (summary fact sheet) is certainly not uniform. But in general the research suggests that people tend to forge more social bonds when they live at higher densities. And, interestly enough, those social bonds can be protective of health—meaning that it’s possible that living near your neighbors can actually improve your health outcomes, at least on average.
The problem with these kinds of studies, however, is that it’s very difficult to tease apart cause and effect. There’s a good chance that people self select into communities that reflect their values. Those who want to socialize may want to live near a vibrant walkable commercial center (or, if this new study is correct, in a lower-density community with many people similar to them.) And there are the usual confounders like race, education, and income, all of which play a role in how many social interactions a person is likely to have.
I find this stuff fascinating, but despite a fair bit of exposure to the research, I can’t make up my mind about how important sprawl may be to social capital. See, for example, my ramblings here and here. If folks have thoughts on the subject, I’d welcome ideas and references for further study.