SNA 101: Finding SNA Data Sets to Play With

SNA 101 posts are meant to be instructional. If you are new here, please refer to the introduction before diving in!

***

Suppose you want to do some freelance social network analysis of illicit terror cells to pass the time. But suppose, like me, you possess neither a secret clearance nor a cadre of intelligence collectors providing you with data. Don't fret! There are many SNA scholars on the net who have done most of the work for you.

Case in point: Stuart Koschade.

Stuart Koschade, an absolute stud when it comes to SNA, provides extensive analysis of various illicit terror cells in his PhD Thesis "The internal dynamics of terrorist cells: a social network analysis of terrorist cells in an Australian context." What makes this paper particularly useful for the amateur social network analyst is the fact that he provides both sociograms and sociomatrices of his subjects. For example, in his analysis of terror organization Jemaah Islamiyah (JI) during their Bali operation, he provides a "sexy" sociogram of the network:

And then he provides the very unsexy, workman-like sociomatrix that made the sociogram possible:

I talked about the interplay between sociograms and sociomatrices in a previous post. This is another opportunity to do so. Let's look closely at how Koschade's two visualizations refer to the same data. Focus on the actor named "Feri." In the sociogram, he is the lone node at the very top of the image. He is linked to 6 other actors (i.e., his degree centrality = 6). If you look at the row titled "Feri" in the sociomatrix, reading left to right, you will notice a "1" in the cells referencing those 6 actors he is linked to in the sociogram, and then a "0" for all other cells.

Google "social network analysis" and "terrorism" and you will find many SNA data-sets to analyze and play with. Uncloaking Terrorist Networks by SNA guru Valdis E. Krebs is a classic article on the topic, but for me, Koschade's work is the gold standard because he provides both a sociogram and a sociomatrix of his work. Why is this so important?

1) SOCIOGRAMS COMMUNICATE IDEAS QUICKLY! The sociogram provides your customer a striking image of the network that provides immediate insights. For instance, looking at Koschade's sociogram, you are probably thinking "Who is that Sumadra guy in the middle? That dude is a broker. That dude is important. We oughta' kill that dude! I oughta' kill that dude!" 

But, sadly...

2) SOCIOGRAMS LIE! Take a look at the following sociogram:

Which of these nodes is the most central and well connected actor?

You might be tempted to say node "6." After all, 6 seems to be in the middle of all the action. But the reality is, all of these nodes have the exact same degree centrality (i.e., 5 links each). Go ahead about count how many links actor "6" has. Then count how many links any of the other actors have. Tricky, huh? Providing a sociomatrix provides your customer (or other SNA enthusiasts) a means of checking your work.