Any random email user is connected to anyone else through a few intermediary acquaintances, American sociologists find.
Their publication in the journal Science confirms that the universe is small, as originally proposed in the 1960s with the "six degrees of separation" theory.
Researchers at Columbia University asked 61,000 Internet users in 166 countries to forward an e-mail to their acquaintances and friends, with the aim of the message ultimately reaching one of 18 final targets.
These included a records inspector in Estonia, an IT consultant in India, and a Norwegian army veterinarian.
Messages took just five to seven intermediate recipients, on average, to reach their final destination.
Global Networks
According to Dr. Duncan Watts and his colleagues, the experiment confirms that social networks are truly global.
“This idea of a small world can explain all sorts of connections,” the mathematical sociologist told Reuters. It can, for example, explain epidemics, fashion, stock markets and companies that manage to survive as the world changes, Duncan explains.
The idea of the "small world" first appeared in a publication by social psychologist Stanley Milgram in the American magazine Psychology Today in 1967.
The researcher had asked random volunteers in the Midwestern states of the US to help deliver some letters to a stockbroker in Boston on the East Coast.
The volunteers could not mail the letters, but had to hand-deliver them to someone they knew who they believed was likely to be connected to the broker.
The letters reached their destination through six intermediaries, on average—hence the "six degrees of separation.".
Duncan even argues that the success of sending a message does not depend on how many acquaintances the original sender has. “We conclude that social search is based on equality, and its success does not depend on a minority of exceptional individuals,” the researchers write.
