We were wowed by the amount of time and energy Philip put into gathering the voting information on which he based his map. Great job. He provides both a solid example and a candid discussion of his central point: It makes a big difference wheher you base your judgment about the competitiveness of a map on actual voting data vs. registration data.
We liked that he had the courage of his convictions to challenge the model that Draw the Lines was using in this competition round. (And we don’t disagree that including election data in the tool would add an important dimension. It just wasn’t feasible logistically for us to do that this spring.)
When I submitted my map to last year's contest, I argued for my submission by underlining the value of competitive elections. One frustration I had when drawing that map concerned the data available for measuring competitiveness. District Builder, the Draw the Lines tool, calculated these values on the basis of party registration data, not actual voting patterns, which can differ markedly; a district with a Democratic registration advantage in SW or NE PA might in fact feature lopsided *Republican* margins of victory.
Indeed, political science has long understood that voter registration is a lagging indicator, which does not always correlate to individuals' partisan identification, let alone voting behavior. But this is not merely an academic quibble; the question of whether nonpartisan redistricting commissions ought to take partisan voting data into account is a live issue, with some arguing that such commissions ought not to consider partisanship.
I decided to submit a map that specifically took voting data into account, in order to demonstrate the difference taking such data into account makes. I believe any effort to counteract gerrymandering for partisan advantage is hobbled insofar as it fails to take into account the same partisan voting data that those who draw partisan gerrymanders rely on. Although this was a more laborious process, I was able to design a map that includes nine actually competitive districts when measured by voting data, seven of which are close to pure toss up districts.