Rationality and voting

I’ve written about rationality and voting before, but I still see some confusion out there (for example, in some of the discussion here). Our discussion is here (with longer article here). But let me try to clarify briefly right now.

I do not claim that voting is always rational or even mostly rationally motivated. What I do object to is the claim that voting is essentially never rational. For someone living in a swing state who cares about the outcome, I think voting in the presidential election is a very rational thing to do: a small cost and something like a 1-in-10-million chance of altering the history of the world. It’s certainly a bet I’d be glad to take.

But I’ll be voting in New York, where my vote has almost zero chance of making a difference, so why do I do it? Not for instrumentally rational reasons. I do it for the usual reasons of civic duty, supporting the legitimacy of the electoral process, etc. Again, I’m not saying that all voting or even most voting is rational but that voting can be rational in many important settings (including presidential voting in Ohio, and congressional and senatorial voting in all sorts of places).

I’d also like to address the objection that sometimes arises (for example, in here) that one vote never makes a difference, because if the election were decided by one vote, there’d be a recount anyway. This argument is wrong, as we discuss in the appendix to this article (turn to page 674) for details. We discuss how our decisive-vote calculations are reasonable, even for real elections with disputed votes, recounts, and so forth. We show this by setting up a more elaborate model that allows for a gray area in vote counting, and then demonstrating that the simpler model of decisive votes is a reasonable approximation.