Triadic Closure/Facebook ...laboratory for the study of friendships

Article link: http://www.nytimes.com/2007/12/17/style/17facebook.html

The article explains how the popular social networking site is increasingly being used by academic researchers to study friendships.
The author, Rosenbloom quotes Nicholas Christakis, a Harvard sociology professor: “Our predecessors could only dream of the kind of data we now have.” While there are legitimate concerns that some of the 58 million Facebook users may not know their habits and preferences are being tracked, never before have social scientists had such a fertile source of information to on the nature of our friendships.

Also, the article mentions that researchers at Harvard and UCLA are using Facebook to examine the concept of triadic closure: whether your friends are friends of one another. Although the phenomenon was first described by a sociologist named Georg Simmel as long as a century ago, there were few empirical studies. Using Facebook as a laboratory, social scientists are studying triadic closure---which one day may shed light on the exclusionary social cliques that draw circles keeping some people in and others out.

In the past few weeks, the residents in my dorm started playing a game of Assassins. For those of you who don't know, you are assigned a target to kill, but you don't know the identity of your assassin. If you succeed in killing your target, you then proceed to kill his or her target, and so on. It was my first time playing assassins and I noticed that I based on my actions on assumptions I had made through relationships that followed the theory of Triadic Closure.

To make it more complicated, it is also a game of trust, in which relationships that might appear to be positive are, in reality, quite negative. Let's considered the interaction between three players, me, player X, and player Y. My target was player X and his target was player Y. In the world outside of assassins, we are all friends, a stable triangle consisting of only positive links between nodes. Early on in the game, player Y informed me that player X had assassinated her, creating one single negative edge in our now unstable triangle. I believed her. I should have examined this action through the lens of structural balance in social networks to see that this situation was very unlikely...and she was lying. I later learned that X and Y had actually formed an alliance (a positive link), creating negative links to me while appearing to still have positive links. This situation could be reflected in a stable triangle, with two negative links and one positive link, a much likelier situation.

Facebook is also an excellent way to test the small world theory. In fact, you should try to type in someone's name and see if you have any friends in common with you. I have always been surprised that, being in a certain facebook group and clicking on someone that I have never met before from some totally different part of the country as me, will share a friend with me. Moreover, I was reading on wikipedia about an application called "six degrees" on facebook. This application apparently tracks the diameter of all of its users. The average diameter distance between friends is 5.73 and the maximum is 12.

http://en.wikipedia.org/wiki/Six_degrees_of_separation

When looking at facebook and triadic closure, the feature of "People you may know" on facebook is a direct application. This website talks about this feature and the basic scope of what it does and how it works:
http://expertvoices.nsdl.org/cornell-info204/2009/04/09/facebook-and-triadic-closure-legitimate-creepiness/

Interestingly enough, facebook takes social networks to a high level, not only with connecting friends, but with notifying people of who they could be friends with. This is done by calculating the number of social triangles that could be formed between networks of two people. For instance, if Joe was not friends with Jim, facebook would calculate the number of triangles that could be formed between Joe and Jim, and if this was a high rank among possible friends, then Jim would show up on Joe's "People you may know" application. This shows the power that facebook has at analyzing and building social networks.