Three weeks ago (and at the prompting of my colleague Eddie Garrett who heads up Porter Novelli DC’s digital team) I mapped out the interconnections between US Congress Tweeters. We’d been working on a Twitter crawler and it seemed like a good opportunity to test things out on a new data set.

This is a follow-up post. Once again it was prompted by a third party: Christie Findlay at Politics Magazine asked whether it would be OK to print a copy of one of the maps in their March edition. I’ve heard that three weeks are a long time in politics, so I thought I’d better run the crawl again just in case. Also I’ve got a new crawler that uses the proper Twitter API (I can see some of your eyes glazing over you know. Just skip ahead when that happens.) I’d tried it out on the Porter Novelli data set, but welcomed a chance to try it on something more meaty.

So yesterday morning before work I ran the crawl. I use the excellent Tweet Congress as my source of information about which congress people are on Twitter.

Here’s the data I get from them republished as a Google Spreadsheet.

I use Twitter itself as the source of information about who follows whom and who — in turn — is followed by whom. Then my computer does a little analysis on the data I get so that I can put it through our mapping software. Here’s the map. It’s a little too small to see, but if you click on it, it’ll take you to a huge version on Flickr.

It’s probably worth going through some of the features again briefly, just in case you haven’t seen my other maps. Actually, I don’t think I’ve ever really explained them properly.

The arrows show the direction of the relationship. If Senator Susan Collins follows Senator John McCain then there’s an arrow that points from Sen. Collins to Sen. McCain. If Representative Jason Chaffetz (Rep. Utah) and Representative Jared Polis (Dem. Colorado) follow each other then there’s a double-headed arrow between Reps. Chaffetz and Polis.

If they follow none of their peers and none of their peers follows them, then they’re relegated to the bench. In this map the bench is the list of unconnected circles in the upper left corner. For those of you who are comparing this to the last map, one of the interesting things to note is that Senator Hillary Clinton has left the ranks of the Democrat congressperson Twitter folk.

I’m not sure why Rep. Thomas Price (R, GA) and Rep. Steven Driehaus (D, OH) have Twitter handles listed. They aren’t on Twitter as far as anyone can tell. Perhaps it’s a tyop?

So far, so obvious I suspect. And it should be obvious to any US readers, the red circles are the Republicans and the blue circles are the Democrats. This is mildly contrary and confusing to my UK audience who are used to the left-of-centre Democrat analogue Labour Party being red and the right of centre Republican analogue Tory party being blue. It’s like going to France and forgetting that the tap with C on it gives you hot water. For my US readers, you probably know a tap better as a faucet. It’s rather exhausting having to do all this translation.

You’ll notice that the circles are different sizes. If you’re very observant, you’ll probably notice that the large circles have more arrows pointing at them, and that the smallest circles have no arrows pointing at them. For this map I’ve sized the circles by a factor called “indegree” which pretty much translates as “the number of arrows pointing at you.” Indegree is used in network analysis as an indicator of popularity or authority (depending on the circumstances.)

First caveat

This can be pretty spurious when you’re looking at what is (after all) only one communication channel for this network. We have to imagine that congresswomen and men (although it’s mostly men at present) will have opportunities tp communicate face-to-face, on the telephone, and via email, memos and mail and the like. So I have no idea how well this fits the reality. I’d have thought (for example) that Sen. McCain was pretty authoritative — but the Twitter map shows him to be peripheral.

This leads us to our second caveat.

Second caveat

For most of this group, the primary audience is not their peers. It is (rather obviously) their voting public. As we’ll come to see some of them have established some pretty hefty audiences (although none of them is really in celebrity territory yet.) So that probably makes this network even less representative.

Still it’s an interesting exercise. Let’s carry on.

I don’t want to labour this too much. Those of you who regularly read this blog must be getting sick of hearing about betweenness centrality. For those of you who don’t know, then here’s a brief explanation: betweenness is a measure of how important the person is in terms of flow of information. It’s calculated by working out who is on most shortest paths through the network.

If Twitter were the only way that information flowed in Congress, then Representative John Culberson is (still) the single most important person there. Taking him out of the loop would mean that the flow of information would slow down considerably, and that some people would never get the message at all.

Take both him and Representative Neil Abercrombie out of the picture and it’s like something out of West Side Story.

Sharks and Jets

Because every social media expert other than me has written a term paper on “How Obama used social media to win the election”, and because the general social media buzz tends to be slightly Democrat biased we’ve become accustomed to the idea that the Democrats do social media well. That may be true. But all I can say is — looking at this map — you’d never know. Republicans outnumber them 1.6 to 1 on Twitter (once we discount the spectral accounts of Driehaus and Price.)

I’d like to say that the Democrats had made up some ground recently, but they just haven’t. A little more analysis shows the growth in Twitter adoption by two parties. Democrats made a good start, but the Republicans really grew their numbers during June and July last year.

update: I’ve fixed yesterday’s chart. I got the whole Red vs Blue thing the wrong way around again. Thx to EG for setting me straight.

However the new Democrat joiners aren’t really linking to each other. Why is this? If you’re hoping to attract followers, one good strategy is to make the most of your network: their followers are more likely to be interested in what you have to say. More interested, that is than an equivalent control group chosen at random from the Twitterverse. So not joining networks just makes things harder.

Partly of course, we can attribute it to naivety. Most new people coming into blogging, Twitter and the rest see creating content as the hard work. Most people who’ve been doing this for a while know that it’s the promotion and moderation that sucks up your time.

Perhaps we might also attribute this to the point raised in Caveat 2 above — that they’re mostly interested in their electoral constituencies. However, if this were the case then I think we’d expect to find factions (or “cliques” or “clusters”) between congresspeople of the same colour who represent the same state. Nothing obvious there, though (and the data set’s quite small). So let’s stick with the “Twitter newbies” theory for the moment.

How many people follow the Congressmen?

So far we’ve only looked at peer relationships: all the charts and calculations we’ve done so far are based on a much-reduced data set. Experience shows that it’s very difficult to map “all followers” (we end up with something that looks like a hedgehog that’s had a wild party in a cranberry field.) But we can still count followers. Here’s a quick list — you can see that there are one or two superstar congresspeople, but that the rest really aren’t doing even as well as your average journalist.

OK — now let’s assume that these aren’t unduplicated audiences; that there must be several people interested in US politics who follow more than one, many, or all the names on the list. What is that duplication like?

Luckily I’ve just written a little analysis script to look at exactly this sort of question, so I can tell you with confidence that (while the absolute numbers above might lead you to think that the congress Twitterers reach an audience of around 56K) if they all pull together, they actually reach an unduplicated audience of 24K. Of course, now I look at it, I realize that they are unlikely to pull together in this way, and that I should have separated the lists into Republicans and Democrats before I went at this. This is somewhat frustrating — but I can cover it in a new post, I suppose.

Here, then, is the somewhat useless Pareto chart showing the unduplicated reach as though the US were a one-party state.

I’ll come back to this, but if you have questions, you might like to look at this Q&A I wrote over the weekend.