Facebook friend network

The social networking site Facebook lets you see for each of your friends which of your other friends they are also friends with. Of course this changes all the time as more people add each other as friends. Based on today’s information, I connected all my Facebook friends, drawing bigger circles for people who were connected to more of my other friends. Friends with whom I have no other Facebook friends in common are shown as black dots.

There are a few interesting nodes:

One node is gigantic, connecting to about 25 other people. This is Rannie, the driving force behind the bloggers social network in Toronto. That whole big chunk of connected people are almost all Toronto bloggers, who are more likely than others to be connected on Facebook in the first place, because they’re all internet savvy and connected enough (both geographically and socially) to influence each other and convince people to join the site and be their friend.
The Toronto bloggers form small little cliques among themselves, and many have never met, but all of them know Rannie. Rannie is what is known as a “connector“: a hub in a social network. It’s very much like a hub in any other small-world network. If this was a map of airport connections, the hub node would be Chicago O’Hare or London Heathrow.

Another type of node is quite interesting: they connect entirely different social circles. There is, for example, a connection between the small triangular network of Hypothesis editors and the network of people in my orchestra, thanks to a previous orchestra member who is in the same department as a friend of one of the editors. The dividing line between these two networks is hard to see, because the orchestra network, just to the bottom right of the blogger network, isn’t that well connected. Unlike the bloggers, they’re not as obsessed with the internet, and even though most people know each other, they’re not all connected on Facebook. (Interestingly, though, the most connected node within the orchestra network is the concert master.)

These nodes that connect two entirely unrelated groups are called bridges, and as you can see, there is also a bridge between the bloggers and the orchestra. That bridge node is Graham, who played a show with our orchestra last year, and also photo-blogs, connecting him to people in both of my networks.

In any network, both the hubs and the bridges are important. Hubs obviously connect many different nodes, and are efficient spreaders of information. When Rannie didn’t organize blogger meets for a while, nobody did. Some attempts were made, but they failed. We needed a connector, a hub.
But without bridges, information wouldn’t spread to the further outreaches of a network. In social networks, bridges are the people who are able to provide you with new connections outside of your regular networks, and they don’t have to be that extensively connected to be able to do so.

My drawing is a very incomplete social network for various reasons:
-Not everyone is on Facebook. In fact, none of my friends from Holland are. If people in Holland are on any social networking site, they’re on Hyves. Through there I’m connected to all my old classmates and roommates, but none of them are on Facebook. I will map them out one day as well.
-All these people are connected to me, so the single dots and islands are not at all isolated from the rest of the network. They’re only two degrees away from everyone else by way of me.
-I didn’t include anyone who was not connected to me. There is no visible connection here between Hypothesis and my lab, even though these people are all working in UofT labs. Of course I would be able to connect them through Facebook connections, but their mutual friends don’t know me, so aren’t included here.

The concept of hubs and bridges is explained on this site Social Network Analysis and in a previous blog post on easternblot.
Since that post, I have read Linked, and there is a whole chapter on “Hubs and Connectors”. In it is a quote from “The Tipping Point“, by Malcolm Gladwell:

“Sprinkled among every walk of life… are a handful of people with a truly extraordinary knack of making friends and acquaintances. They are connectors.”

When I read that, I immediately thought of Rannie, and after mapping it all out in the drawing above, I have proof! Rannie is indeed a connector.