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SAN FRANCISCO, Aug. 15 (Xinhua) -- Facebook and Yahoo on Monday started to test "six degrees of separation," an iconic social experiment in the 1960s that showed everyone is on average approximately six steps away from any other person on earth.
The current Facebook-Yahoo "small world" experiment, based on more than 750 million active Facebook users, is expected to determine the social path length between two strangers.
Anyone with a Facebook account can participate by going to smallworld.sandbox.yahoo.com and will be assigned a "target person. " The participant will be asked to select one of his or her Facebook friends, whom will be forwarded a message and then pass the message from friend to friend so that the participant will get a message to the "target person" in as few steps as possible.
The study is intended as academic social research and will be published in peer-reviews scientific journal, Duncan Watts, Yahoo' s principal research scientist who is leading the experiment, told San Jose Mercury News.
In the 1960s, American social psychologist Stanley Milgram and other researchers conducted several experiments to examine the average path length for social networks of people in the United States, suggesting that human society is a small world type network by around 5.5 people steps or about six people on average.
It is now currently accepted that there were potential flaws in the so-called "small world experiment" because the conclusions were based on relatively small number of research samples.