The latest release of the Political Data Inc. redistricting package allows us to look at the 2010 election results by contest. So, using the congressional results from last election cycle I was able to construct election results as if the Cook plan had been implemented.
An obvious caveat is that these elections never happened. Incumbents who had an easy ride in the existing lines would be fighting a different battle. But it's also true that the challengers - many of which were unimpressive and unfunded - would be cut from a different mold in a newly competitive seat.
Our friends at the Cook Political Report have released an updated Partisan Voting Index that now includes the results of the 2008 presidential election. They've also made a small change in the formula used to calculate PVIs, and I think it'll be instantly recognizable to SSPers:
To determine the national average for these latest ratings, we have taken the average Democratic share of the two-party presidential vote for 2004 and 2008, which is roughly 51.3 percent, and that of Republicans, which is roughly 48.7 percent. So, if John Kerry captured 55 percent of the vote in a district and Barack Obama carried 57 percent in the district four years later, the district would have a PVI score of roughly D+5. (Emphasis added.)
As we discussed at length, the old PVI formula compared district-level results for the past two presidential elections to nationwide results for only the most recent election. This choice sparked plenty of debate, and some folks even suggested we use our own "SVI" that would compare 2004 to 2004 and 2008 to 2008.
Fortunately, the debate has been resolved. As you can discern from the description above (the key part is in bold), Cook has decided to revise its methodology along the lines proposed by people here. Charlie Cook (an SSP reader, as is House editor David Wasserman) told me he wanted something that was "totally apples and apples," and I agree with the choice. Ultimately, this means that the new PVIs will be about two points bluer than under the old system - e.g., a district that would have been R+10 will now come in at R+8.
You can find the new PVIs by partisan rank in this PDF, as well as by member name and by state/district. There's also a giant-size map and a cool chart showing trends in the PVI over the last decade. (As you'd expect, the number of "competitive" districts, at least on the presidential level, has been shrinking.) Have fun!
Hardly a day - hardly a post - goes by here at the Swing State Project without a reference to the Cook Political Report's Partisan Vote Index, or PVI for short. In the wake of the 2008 elections, SSP's pres-by-CD project has spurred a lot of discussion about how the PVI is calculated and why it's calculated the way it is.
Quite a few people people had a hard time believing my explanation of the math behind the PVI. But you don't have to take my word for it - this is how the Almanac of American Politics explains things:
Cook Partisan Voting Index. Refers to the Partisan Voting Index (PVI) as used by Charlie Cook, Washington's foremost political handicapper. The PVI is designed to provide a quick overall assessment of generic partisan strength. For this volume, the PVI includes an average of the 2000 and 2004 presidential elections in the district as the partisan indicator. The PVI value is calculated by a comparison of the district average for the party nominee, compared to the 2004 national value for the party nominee. The calculations are based upon the two-party vote. The national values for 2004 are George W. Bush 51.2% and John Kerry 48.8%. The PVI value indicates a district with a partisan base above the national value for that party's 2004 presidential nominee. Thus a district with an R+15 is a district that voted 15 percentage points (as an average of its 2000 and 2004 presidential vote) higher for Bush than the national value of 51.2%. Similarly, a district with a D+15 is a district that voted 15 percentage points (as an average of its 2000 and 2004 presidential vote) higher for Kerry than the national value of 48.8%. An X +00 indicates an evenly balanced district. (Emphasis added.)
The boldface sentences confirm my understanding of how PVI works. But why should it be calculated this way? I agree with the majority sentiment that it seems to make more sense to compare 2000 district performance with 2000 nationwide performance, not 2004 nationwide performance. This isn't as big of a deal with the two Bush elections because they were both so close, but comparing Kerry's 2004 district numbers with Obama's nationwide numbers produces some pretty serious gaps. I'd be curious to know what sort of justifications or rationales anyone can come up with for the status quo.
In the meantime, some have suggested computing an "SVI" - a "Swing State Project Voting Index," comparing 2004 to 2004 and 2008 to 2008. In fact, CalifornianInTexas has already gone ahead and started calculating these numbers. For the most part, these will be more favorable to Dems, as the big Kerry minus Obama splits are removed from the equation.
So, I'm asking the community: Should we use the "SVI"? Should it be in addition to the PVI? Are there any pitfalls if we do so? Any reasons not to? Let's hear your thoughts!
DEP Rejects Permit Application for PA Waste / Boggs Township Landfill.
I'm pleased to report the Pennsylvania Department of Environmental Protection has rejected the permit application filed by PA Waste LLC to construct a 5,000 ton per day municipal waste landfill in Boggs Township, Clearfield County. As county commissioner, I've been working over the past 4 years, first with Rex Read and Mike Lytle, and now with John Sobel and Joan Robinson McMillen, to oppose the construction of this landfill in Clearfield County.
