I co-authored a paper in PLoS ONE, published today, entitled Geographic Constraints on Social Network Groups. Essentially, we tried to understand the relationship between position in a social network and physical location by examining social networks at the level of the social group. Here’s a figure from the paper that shows the interplay between the two factors:
And here’s the abstract that gives a sense of our findings:
Social groups are fundamental building blocks of human societies. While our social interactions have always been constrained by geography, it has been impossible, due to practical difficulties, to evaluate the nature of this restriction on social group structure. We construct a social network of individuals whose most frequent geographical locations are also known. We also classify the individuals into groups according to a community detection algorithm. We study the variation of geographical span for social groups of varying sizes, and explore the relationship between topological positions and geographic positions of their members. We find that small social groups are geographically very tight, but become much more clumped when the group size exceeds about 30 members. Also, we find no correlation between the topological positions and geographic positions of individuals within network communities. These results suggest that spreading processes face distinct structural and spatial constraints.
Onnela, J., Arbesman, S., González, M., Barabási, A., & Christakis, N. (2011). Geographic Constraints on Social Network Groups PLoS ONE, 6 (4) DOI: 10.1371/journal.pone.0016939