Scaling legislative roll call votes with wnominate

December 3, 2012

(This article was first published on is.R(), and kindly contributed to R-bloggers)

We’ve used NOMINATE scaling data before here at is.R(), but today’s Gist shows, in just a few lines of code, how to download up-to-date roll call data and run those votes through Keith Poole (et. al.)’s DW-NOMINATE procedure.

It’s really very straightforward — the tricky parts are getting the roll call object in the proper format (if it’s not already) and specifying the polarity option to indicate a conservative in every dimension. Perhaps unsurprisingly, the parties are quite distinct in the most recent Senate data:

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