The Boston Globe “describes some research by MIT students”:http://www.boston.com/bostonglobe/ideas/articles/2009/09/20/project_gaydar_an_mit_experiment_raises_new_questions_about_online_privacy/?page=full
bq. The pair weren’t interested in the embarrassing photos or overripe profiles that attract so much consternation from parents and potential employers. Instead, they wondered whether the basic currency of interactions on a social network – the simple act of “friending” someone online – might reveal something a person might rather keep hidden. Using data from the social network Facebook, they made a striking discovery: just by looking at a person’s online friends, they could predict whether the person was gay. They did this with a software program that looked at the gender and sexuality of a person’s friends and, using statistical analysis, made a prediction. The two students had no way of checking all of their predictions, but based on their own knowledge outside the Facebook world, their computer program appeared quite accurate for men, they said. People may be effectively “outing” themselves just by the virtual company they keep. … “Even if you don’t affirmatively post revealing information, simply publishing your friends’ list may reveal sensitive information about you, or it may lead people to make assumptions about you that are incorrect,” said Kevin Bankston, senior staff attorney for the Electronic Frontier Foundation, a nonprofit digital rights organization in San Francisco. …
bq. The project, given the name “Gaydar” by the students, Carter Jernigan and Behram Mistree, is part of the fast-moving field of social network analysis, which examines what the connections between people can tell us. … The researchers treated their data anonymously, never using names except to validate their predictions during data analysis. The only copy of the data is on an encrypted DVD they gave to a professor, and they said they got the approval of an ethical review board at MIT. The students, who have since graduated, discussed the paper with the Globe, but did not provide a copy of it because they are hoping to have it published in a journal.