Monday, November 2, 2020

Why You Should Probably Not Vote to Change the Outcome

There’s a great new paper in Philosophy and Public Affairs by Zach Barnett titled “Why You Should Vote to Change the Outcome.” But contrary to some of the claims I’ve seen people make (claims *not* made by Barnett in the paper, I should note), the paper doesn’t show that everyone should vote tomorrow to change the outcome. 

First, the paper focuses on the probability that your vote will be decisive. But with the Electoral College, you can cast the decisive vote in your state without changing the outcome of the election because your state’s electoral votes may not be needed.

Furthermore, depending on your state, the odds of an upset may be far lower than in Barnett’s cases (check out the latest odds here). As Columbia statistician Andrew Gelman quips, “The prediction markets will give you 34-1 odds that Biden wins California, which would be a fair bet if Trump had a 3% chance of winning California, which is approximately 3 percentage points higher than it should be.” 

Indeed, as I wrote in my book: "Even if your vote does defy the odds and makes or breaks a tie, the result would be a recount—a recount whose final tally will surely differ from the initial one. And we’re still not done: if history is any guide, a razor-thin margin of victory will send the election to the courts. As Stephen Dubner and Steven Levitt note,

The closer an election is, the more likely that its outcome will be taken out of the voters' hands—most vividly exemplified, of course, by the 2000 presidential race. It is true that the outcome of that election came down to a handful of voters; but their names were Kennedy, O'Connor, Rehnquist, Scalia and Thomas. And it was only the votes they cast while wearing their robes that mattered, not the ones they may have cast in their home precincts.

Thus, the outcome of even an extremely close presidential election will probably not be decided by your vote, but rather by lawyers and judges."

 

Lastly, Barnett assumes that “The average social benefit of electing the better candidate is more than twice as great as the individual cost of voting.” I have no doubt that this is often true; the problem is figuring out the total long-term value differences of the two potential presidential administrations before casting your vote. Since we are talking about global-scale impacts playing out over decades, it’s hard to have much confidence in our judgment—especially when we consider how partisan bias distorts our beliefs about the comparative effectiveness of candidates and policies. If you *are* confident in your ability to make these predictions, you could win quite a bit of money in betting markets. (I should say that I am less skeptical of the value difference between candidates in this election, as I believe we have very good reasons for thinking that Biden is far better than Trump.) 

 

So at most, this argument shows that only some people should vote to change the outcome--in particular, only voters in the following states: Florida, Arizona, Georgia, North Carolina, Iowa, Ohio,Texas. The rest of us may stay home.