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“We are all a lot closer to Kevin Bacon than we thought.
A few months ago, we reported that a Yahoo team
planned to test the six degrees of separation theory on Facebook. Now,
Facebook's own data team has beat them to the punch, proving that most Facebook
users are only separated by four degrees."
"To test the six degrees theory, the Facebook
researchers systematically tested how many friend connections they needed to
link any two users. Globally, they found a sharp peak at five hops,
meaning that most pairs of Facebook users could be connected through four
intermediate people also on Facebook (92 per cent). Paths were even shorter
within a single country, typically involving only three other people, even in
large countries such as the US."