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'Six degrees of separation' theory tested on Facebook
Yahoo! and Facebook are to test the “six degrees of separation” theory and investigate how social networks are affecting how closely people are connected worldwide by updating a famous experiment.
The pair are conducting an online version of the social psychologist Stanley Milgram’s small world experiment, which he began in 1967.
Volunteer “senders” will be given the details of a “target”, another of Facebook’s more than 750 million members, who they will not know.
The senders will send a message for the target to one of their friends, who will forward it to one of their friends and so on, until it reaches the target. Each link in the chain will be encouraged to pick the friend they think has the best chance of knowing the target.
In the original 1960s experiment, Stanley Milgram did the same with letters. He found that people in the United States were connected via an average of 5.5 others, which in part gave rise to the “six degrees of separation” theory in popular culture.
“You really couldn't have done this until very recently,” Duncan Watts, Yahoo's principal research scientist, told MercuryNews.com.
“It's a milestone, in terms of it's the kind of research question you can answer now that you could have imagined 50 years ago but that you couldn't have answered 50 years ago, or even 15 years ago.”
All Facebook users are being invited to participate in the experiment, which its planned will lead to a peer-reviewed scientific study. The dominant social network also believes it could have commercial implications.
“Facebook depends on its connectedness, and the fact that users are connected to each other and users are connected to brands, enables the diffusion of important messages, a big part of which is our advertising platform," said Facebook’s chief data scientist Cameron Marlowe.
A game loosely based on the “six degrees of separation” theory and the small world experiment has also thrived online. In “six degrees of Kevin Bacon”, players have to link any actor to Kevin Bacon in as few steps as possible.
The game is thought to have been popularised on newsgroups, beginning in 1994 with a post entitled “Kevin Bacon is the centre of the universe”. IMDB, the film database, now lists each actor’s “Bacon Number” alongside their credits.