cluelessresearch.com

One of my main research areas is spatial analysis of roll call data. If you keep on reading this site you will learn more about it then you would like to know about it. At this time I only itend to show one of the cool things it can do, namely identifying the left-right positions of parties in legislatures using individual deputies roll call decisions.

The following figure plots the region where the central 50% of the deputies of each party are expected to be in. You can get the roll call votes I used to generate the map right here .

Spatial Map 52nd Legislature (until May 2005).

The positions are not based on any kind of substantive knowledge about either roll calls or deputies (and that’s a good thing.) It pictures a recurring finding about Brazilian politics: there is an underlying structure with the PT and the PFL at extremes of the space. This, as I showed in my master thesis back in 2000, has been true at least since 1989.

Within this stability there’s much change. Of note is the PDT (usually thought as a left party) placement to the right of the PMDB (considered a “center right” party by most). These positions were reversed during the Cardoso years. So, is the cup half full (party positions are stable) or half empty (there is too much change for them to make sense)?

The ideal points and standard errors are also available in the data section.