FLOTSAM & JETSAM: Down East Diary: Can you trick instant runoff voting?

Sunday, September 18, 2011

Down East Diary: Can you trick instant runoff voting?

Sam Smith

A couple of Portland friends have raised the question of what is the best way to cast your ballot in an instant runoff vote with 15 candidates, as they will have to do shortly. For example, should you vote for the one most likely to come in last so your second choice will zoom to the top in the next count? What is, in short, the best way to game the ballot?

I have a vested interest in this matter since the modern IRV movement started in my living room back in 1992 thanks to Rob Richie and John Anderson. Since then I’ve largely served as an journalistic enthusiast, yet proud to have served even such a minor part is getting such a major movement going.

I have never, however, had to deal with the question of how one decides between 15 candidates, a number large enough to invite the mathematically inclined to come up with all sorts of interesting theories.

IRV is not perfect, but in a state in which we currently have a governor elected by only 39% of the voters, substantial improvement will pass as a major alternative and IRV is certainly that.

In fact, it seems to be the best alternative anyone has come up with that they could also convince others to agree to try out.

If, for example, you start to read the arguments for some of the alternatives, you may find something like this:


Slowly, it may dawn on you that coming up with the perfect mathematical solution in a country where only about 57% of the voters turn out even to elect a president might not be the best route to a fairer system.

What is needed is the fairest system voters can understand and also feel inclined to use. Which is why IRV has been making such headway.

But there still remains the question of what one does at the voting booth, given the large number of candidates. Are you in a democracy or a casino, some may wonder, and hence the natural urge to game the system.

The problem is that even if you come up with a mathematically appealing answer, you may be in a tiny minority that agrees with you, hence you can easily blow your vote just so you can brag about how smart you were.

It’s not unlike the relationship between perception and reality in the stock market. You may rightfully have found a stock that deserves to soar, but if few agree, you will be no better off than if you weren’t all that perceptive.

So the real question is: what is the average bloke going to do at the voting booth? I would wager that this voter will only have even a mild opinion about less than a half dozen of the candidates and the reason for this will be, in part, because they are the ones who are most popular and have gotten the most coverage.

Of course, there is also your friend Oliver B. Chortleywell who is running as well, and you owe him, after all these years of drinking together, your first place choice. So you vote for a candidate nobody knows and then, typically, join the crowd in your second or third choice. Still, since there are just 43 of you in Portland, you have little effect on the second ballot except to move the choice up to the person with 51 votes who barely beat Oliver, and so forth until we come up to real numbers.

Meanwhile, at the other end, A. Bloke doesn’t like either of the leading candidates but to prevent the worst from winning, he votes for the lesser of the evils and then, for second choice, selects his true love. In a partisan race that might mean a Democrat voting for a Green for second place, and a Republican voting for a Libertarian. But meanwhile the Dems and the GOP still have Bloke’s first place ballots.

Now the Libertarians and the Greens are doing a sort of reverse play: choosing their true loves first, and then casting a reluctant second or third ballot for the leading candidates.

You are not going to bust this system by voting first for Oliver B.Chortleywell. All you’ve done is taken your first choice and moved it down to second.

Have I already confused you? Good. Then just act like a normal rational person (or any grade school kid for that matter) and select your real choices in order.

As IRV expert Caleb Klppener explained at a Portland meeting, “You should rank candidates until you’re indifferent about the remaining candidates. You should keep ranking them until you just don’t care who wins among the candidates who are left. . .

“The question has come up: Can you game the system. . . The best, most calculating voter in the world will vote exactly the same way as the directions indicate — exactly the same way as somebody who doesn’t know anything about the system.”

And as the Portland Daily Sun noted:

“Contrary to what some candidates (and no doubt many voters) believe, second choices are only valuable to a candidate if they receive as many or more first choice votes. The reason being that candidates need first choice votes to avoid being eliminated during the instant runoff. You cannot win by being everyone’s second choice.”