From the weblog Ascription is an Anathema to any Enthusiasm, which is big on graphical representations of statistical data, comes Slicing and Dicing the Senate (via). It displays and explains a series of charts from VoteView.com, titled The Current U.S. Senate: Optimal Classification Estimates of Ideal Points and Cutting Lines for the Last 50 votes.Don’t that just sound like salted peanuts? But it really is interesting:
Because the majority of my readers live in the United States: for “weaker and more numerous economic actors,” read “you; as in, you personally.”
Each point on the charts represents one US Senator; they don�t move. The idea of this technique, �Optimal Classification Estimates�, is to reduce each legislator to two numbers and them pin them onto that graph. It�s extremely reductionist, but it works. The lines slicing thru the chart illustrate how voting proceeds on various bills. A line running from top to bottom reveals that a bill was decided largely on economic issues; while a line running left to right is a bill that was decided on social issues. The Democrats on the left are economically liberal, i.e. they tend to look out for the weaker and more numerous economic actors. The Republicans on the right are economically conservative; look after the economically large, but few.
That’s a profound point. I’ve strongly suspected it was so, but didn’t have the numbers.
The chart on the right shows how well the model works. The handful of points shown there are Senators whose votes didn�t fit the model. …
The model is extremely accurate: around 95% these days. Amazingly, you don�t actually need two axes; you will get 90% accuracy with a single axis that runs almost top to bottom, but slices slightly at an angle. You can see the entire Senate sorted into that ordering here. For example Joe Liberman isn�t the most conservative Democratic Senator; there are a handful who are more to the right than he is.I�ve written about this model before, and I keep coming back to it because it totally changed the way I think about politics. It�s all economic; all the noise about social issues never actually flows thru into the legislative agenda.
This also explodes the idea that there’s no real difference between the Democrats and the Republicans. That’s what Enthusiasm was writing about in that earlier essay. There is a difference. It is durable and consistent. Republicans make a lot of distracting noise about social issues that command the attention of many middle-class and working-class families; but when they turn from talking to acting, they cater to a small number of very rich people. Odds are, none of them are you.