Facebook brings world closer by two degrees

Many of Facebook's 800 million-plus users can be connected via just four shared contacts, the company has revealed.

A recent survey from Facebook and the Università degli Studi di Milano has found that while users tend to concentrate their friend groups around a similar age and locational range, accounts on different sides of the globe can often be linked via just four for five individuals.

The finding contrasts with the commonly held notion of six degrees of separation between any two individuals. Facebook has found that its users average just five intermediary contacts, or four degrees of separation, and that the average number of "hops" between users has dropped over the past three years.

"While 99.6 per cent of all pairs of users are connected by paths with five degrees (six hops), 92 per cent are connected by only four degrees (five hops)," the company said in a report posted to the Facebook blog.

"And as Facebook has grown over the years, representing an ever larger fraction of the global population, it has become steadily more connected."

Despite the growing connectivity of users around the globe, researchers found that users' immediate circles remain highly localised. The report found that users preferred to stay within their immediate region for friends, with an average of 84 per cent of connections in their own country.

Additionally, users tended to stay within a common age range on their friend lists, with most connections at or near the user's own reported age.

The result, say researchers, is a landscape which has seen users become increasingly conected as a whole while still keeping to general trends of localisation among users.