Ballot order effects in the news; I’m skeptical of the claimed 5% effect.

Palko points us to this announcement by Marc Elias:

BREAKING: In major court victory ahead of 2020, Florida federal court throws out state’s ballot order law that lists candidates of the governor’s party first on every ballot for every office. Finds that it gave GOP candidates a 5% advantage. @AndrewGillum lost in 2018 by .4%

Is anyone really saying that being first on the ballot is worth 5% in a high-profile general election for governor?

OK, following the links, I see this post by Joanne Miller linking to some pages from the court decision. Here’s a key passage:

I’m skeptical that ballot order would swing the vote margin in the Florida governor’s race by 5 percentage points.

I discussed the general topic a couple years ago, in the context of the presidential election:

Could ballot order have been enough to cause a 1.2% swing? Maybe so, maybe not. The research is mixed. Analyzing data from California elections where a rotation of candidate orders was used across assembly districts, Jon Krosnick, Joanne Miller, and Michael Tichy (2004) found large effects including in the 2000 presidential race. But in a different analysis of California elections, Daniel Ho and Kosuke Imai (2008) write that “in general elections, ballot order significantly impacts only minor party candidates, with no detectable effects on major party candidates.” Ho and Imai also point out that the analysis of Krosnick, Miller, and Tichy is purely observational. That said, we can learn a lot from observational data. Krosnick et al. analyzed data from the 80 assembly districts but it doesn’t look like they controlled for previous election results in those districts, which would be the obvious thing to do in such an analysis. Amy King and Andrew Leigh (2009) analyze Australian elections and find that “being placed first on the ballot increases a candidate’s vote share by about 1 percentage point.” Marc Meredith and Yuval Salant (2013) find effects of 4-5 percentage points, but this is for city council and school board elections so not so relevant for the presidential race. A Google Scholar search found lots and lots of papers on ballot-order effects but mostly on local elections or primary elections, where we’d expect such effects to be larger. This 1990 paper by R. Darcy and Ian McAllister cites research back to the early 1900s! . . .

Based on the literature I’ve seen, a 1% swing seems to be on the border of what might be a plausible ballot-order effect for the general election for president, maybe a bit on the high end given our current level of political polarization.

Given that I thought that a 1% effect was on the border of plausibility, you won’t be surprised that I think that 5% is way overstating it, at least for a major election. Sure, governor is less major than president. But, again, in this era of polarization I doubt there are so many more swing voters available for that race either.

0.4%, though? Sure, that I believe.

So, yes, I believe that ballot order was enough to swing the 2018 Florida governor’s election. And, more generally, I favor rotated or randomized ballot orders to eliminate the ballot order effects that are there. This is a bias that can be easily and inexpensively removed; it seems like a no-brainer to fix it. Whether this is a matter for the courts, I don’t know.