Sociologist Fabio Rojas just introduced GMU economists to diagrams of social networks. These diagrams provide a neat way to quickly show who knows who, who knows people who know people, and who knows everybody.
Rojas presented new data on networks of Iraq war protestors. But I'm a lot more curious about the libertarian branch of the Vast Right-Wing Conspiracy (V.R.W.C.), especially since we've got a great new data source: Brian Doherty's Radicals for Capitalism. If Brian had supplied one network diagram for each of the major decades he covers, what would they have looked like?
In the 20's through the 30's, a network diagram of the libertarian movement would have been full of "singletons" - isolated libertarians who were astonished to meet another, because each thought he was the only one.
In the 40's and 50's, a couple major nodes started to emerge. Leonard Read and his Foundation for Economic Education became a major clearinghouse for libertarian thought. Meanwhile, in NYC, Ayn Rand and Murray Rothbard started up fairly independent social networks, albeit with vague ties to FEE and each other.
In the 60's, Rothbard and his group hooked up with a series of left-wing social networks, while FEE and Rand steered clear of them.
In the 70's, previous libertarian networks were eclipsed by the Libertarian Party, the Cato Institute, and Reason Magazine. Initially, these were all closedly connected. But by the 80's the Libertarian Party had begun to be marginalized. Furthermore, Rothbard's split with Cato created a major new node, the Ludwig von Mises Institute, with limited ties to other libertarian centers.
Ultimately, I'm not sure how much sociologists' network diagrams add to a rich history like Doherty's. But it would be very nice if someone other than me assembled Doherty's research into a nice data set, fed the data into standard sociology software, and posted the diagrams.