A Tangled Web We Weave

You may have heard of the “six degrees of separation” concept. The idea is that every person on Earth has a web of social contacts so interwoven that it would only take six people or less to get from any one person on Earth to another.

For example, if I was a farmer in Idaho and I was tasked with getting a message to a stock broker in New York, I could ask my wife who knows a relative in New York who knows an old friend who works on Wall Street who knows a colleague who knows this particular stock broker. The degrees of separation for this example would be five, as it takes five steps to get from one person to another. The theory is that, on average, any two people can be connected in less than six steps.

An outcropping of this theory has been applied to the actor Kevin Bacon. The “Six Degrees of Kevin Bacon” is a game that was developed utilizing the wide variety of roles that the actor has been in and people who he has worked with. The goal of the game is to get from any movie star to Kevin Bacon in under six steps. It is a fun game to play with your friends, especially if you are a film nerd (or have access to IMDB).

Via Wikipedia

Bacon Numbers

Of course, there just happened to be some researchers sitting around who decided to take this game to the next level. What they did was take all of the actors and actresses listed on IMDB and cross-reference them so that a vast network would appear, showing every listed actor’s connections to Kevin Bacon. This led to the development of the “Bacon Number.”

The Bacon number of an actor or actress is the number of degrees of separation he or she has from Bacon, as defined by the game. The higher the Bacon number, the farther away from Kevin Bacon the actor is.

The computation of a Bacon number for actor X is a “shortest path” algorithm:

• Kevin Bacon himself has a Bacon number of 0.
• Those actors who have worked directly with Kevin Bacon have a Bacon number of 1.
• If the lowest Bacon number of any actor with whom X has appeared in a movie is N, X’s Bacon number is N + 1.

Here is an example, using Elvis Presley:

• Elvis Presley was in Change of Habit (1969) with Edward Asner
• Edward Asner was in JFK (1991) with Kevin Bacon

Therefore Asner has a Bacon number of 1, and Presley (who never appeared in a film with Bacon himself) has a Bacon number of 2.

This is all well and good, but the interesting result comes from computing the average Bacon Number for all actors and actresses. It turns out, far from being six degrees away from Mr. Bacon, the average Bacon number for all IMDB listed actors turned out to be only 2.989. This that, on average, in around three steps any actor or actress in Hollywood can be linked back to Bacon.

I’m glad that science and mathematics can shed light on these important mysteries. But that also means that if you are playing the “six degrees of Kevin Bacon” game, you should be only needing around three moves per round. Otherwise, scientifically, you suck.