## Yahoo, Facebook Test "Six Degrees of Separation" 228

An anonymous reader writes

*"Yahoo has partnered with Facebook to test the iconic social experiment known as 'six degrees of separation' (everyone is on average approximately six steps away from any other person on Earth). The goal of the Small World Experiment is to determine the social path length between two strangers by tapping into the world's largest social network and its 750 million users, each of whom have an average of 130 friends."*Looks like a fun project, but not quite as useful as knowing how close you are to Kevin Bacon.
## Re:Travelling Salesman (Score:5, Informative)

It's not a travelling salesman problem, it's a shortest path problem, and as such is much easier. For the distance between two specific people, you'd need the Dijkstra algorithm, and for the distance between any two people, you could use Floyd-Warshall. This one is in O(n^3), where n is the number of users; that's a big number, but it's nowhere near the (supposed) complexity of the TSP.

## Re:Travelling Salesman (Score:5, Informative)

This has been done before. There used to be a site called Six Degrees, which was a social network that showed your contacts at various distances.

Which was swallowed by Orkut. Which was swallowed by Google.

By the way, the original theory is that six degrees is the _maximum_ distance between any two living humans, not the average.