Last week Duke sociologist Kieran Healy had a fun and informative post showing how much information about social networks can be gleaned from so little metadata. Metadata have been in the news lately with the disclosure of Prism the US Government's communication surveillance system. Healy's post shows how knowing only what groups individuals belong to and a little matrix arithmetic that individuals can be "linked through the groups they belong to [and] groups can be linked by the people they share". Using data from the book "Paul Revere's Ride" by Fischer, Healy produced the basic image above showing the links between various Colonials through the clubs, committees, caucuses, etc that they belonged to. In particular this plot shows people that serve as bridges between the groups. I've added the portrait of Paul Revere, a central bridge, "ready to ride and spread the alarm", to many political groups and marking him as a notable Colonial traitor to the British Crown of the 1770s. Healy also has a plot showing the links between the groups. So much information from so little metadata. We've used other similarity plotting techniques here to cluster the Justices of the Supreme Court.
(The follow-up to Gym Freqs, promised last week, will appear next week).
