Strategy in IRV



  • IRV proponents say it somehow defies Gibbard and you can vote your sentiments and not expect to get bitten as a result. Reporter David Leonhardt with the New York Times, on the other hand, writes about strategy with what is called RCV (meaning IRV, however), with examples from real life. This comes in a newsletter from the Times that you can sign up for even without being a paid subscriber to the paper. Since they publish his piece outside the paywall, maybe I can just paste in a copy of it below, and not get crucified on account of my violating their copyright.

    By David Leonhardt

    Good morning. Ranked-choice voting is growing. We offer a strategic explainer.

    A voter casts her ballot in the New York mayor’s race last weekend.Desiree Rios for The New York Times

    A different kind of election

    New York City’s mayoral campaign is one of the highest profile instances of a ranked-choice election in the U.S. Rather than selecting only one candidate, voters can instead choose up to five and rank them.

    The system has some big advantages. In a traditional election, people who vote for a long-shot candidate — like Ralph Nader, the Green Party presidential nominee, in 2000 — can end up hurting a top-tier candidate — like Al Gore that year. With ranked choice, progressive voters could have listed Nader first and Gore second. Once Nader failed to finish in the top two, the final round of the election would have reallocated his voters to their second choice, which often would have been Gore.

    (Ranked choice is also known as instant-runoff voting, because people vote only once. The various “rounds” of voting all occur during the counting of ballots.)

    The basic idea is to allow people both to select their favorite candidate and to indicate their preferences among the other candidates. That combination can allow the most broadly popular candidate to win the election, while also making clear the full spectrum of voters’ views. If Nader had received, say, 20 percent of first-place votes in 2000, it could have signaled the appeal of his platform and inspired other progressives to run in 2004.

    For these reasons, ranked-choice voting can seem as if it eliminates the need for strategic voting. But it doesn’t. Even with ranked choice, voters sometimes should consider more than their own preferences.

    Today’s newsletter offers an explainer — and not just because of New York. Ranked choice has been growing recently, with Maine using it in federal elections since 2018 and Alaska set to begin doing so next year. More than 50 cities — including Oakland, San Francisco and Minneapolis — have also decided to use it, as have state parties in Kansas, Virginia and elsewhere.

    Ranked choice has obvious appeal when many people are dissatisfied with establishment politicians and parties.
    The Alaska dilemma

    To make sense of the complexities, I asked for help from Nate Cohn, who analyzes elections for The Times. Nate suggested we start by looking not at New York’s Democratic mayoral primary, which has eight major candidates, but at a simpler race — next year’s Senate election in Alaska, which appears to have three leading candidates.

    One is Lisa Murkowski, the Republican incumbent who occasionally breaks with her party (such as on Obamacare repeal and Donald Trump’s second impeachment). Another is Kelly Tshibaka, a Trumpist Republican. The third is Al Gross, an independent who would likely be a de facto Senate Democrat.

    For many Alaska Democratic voters, the order of preference seems obvious: Gross first, Murkowski second — and definitely not Tshibaka. Yet there is a major potential downside to voting that way.

    If early polls, like this one, end up being correct, Murkowski could receive fewer first-place votes than either Gross or Tshibaka. Murkowski would then be eliminated, and her votes would be reallocated. Once the second-choice votes were counted, Tshibaka would easily beat Gross.

    By The New York Times | Source: Change Research

    But if some of Gross’s supporters instead listed Murkowski first, she could receive the second-most first-choice votes and qualify for the final round. In that round, she might beat Tshibaka and win re-election.

    This situation creates a dilemma for Democrats: Should they list Gross first, hoping that the polls are wrong and he can win? Or should they list Murkowski first, trusting the polls and supporting the more moderate Republican? The problem has no perfect answer.
    The choice for New Yorkers

    The broader lesson is that when top candidates tower over the rest — as Gore and George W. Bush did in 2000 — there is little downside to listing another candidate first in a ranked-choice election. But when there is more uncertainty, strategy matters. In an election like Alaska’s, voters may want to list their second or third choice at the top of the ballot, to help that candidate make the final round.

    The New York mayor’s race remains highly uncertain, partly because the quality of the polling is unclear, as Nate notes. As a result, there are two reasonable approaches for voters to consider.

    The first is to ignore strategy and simply rank your favorite candidates, one through five. The argument for this approach is that ranked-choice voting is so new that nobody knows what will happen. It would be a shame to outsmart yourself and help defeat the candidate you think would make the best mayor.

    The second approach is to be strategic. On Monday, the well-regarded Marist Institute for Public Opinion reported that only four candidates — Eric Adams, Kathryn Garcia, Maya Wiley and Andrew Yang — were the first choice of at least 10 percent of voters. By listing one of them first, you could help her or him survive until the final round and possibly win. By choosing anybody other than those four, you may have little say over who wins.

    A final piece of advice, from Nate: You can maximize your influence — without hurting your top choices — by filling out all five spots on your ballot. “In such a wide open race, ranking more people increases the chance that your vote counts,” he says.

    For more:

    Critics say that ranked-choice voting can sometimes lead to strange outcomes and that a better method is “approval voting,” in which people vote thumbs-up or thumbs-down on each candidate.

    Rob Richie, an advocate for ranked choice, responds that every system has downsides, as the Nobel-winning economist Kenneth Arrow helped show. “Every nonranked system has far greater problems,” Richie told me.

    Here is Nate’s guide to the New York mayoral race, as well as a series of interviews with the candidates, by Times Opinion. And here is a preview of tonight’s debate.



  • Rob is such an underhanded person. He knows for a fact that Arrow's Theorem only applies to ranking systems.

    Anyway, yes there is this strategy but it is rare that the polling is clear enough that it works. People tend to say that IRV is such a bad system that it evades the ability to game it. Since it is polarizing, nonmonotonic and majoritarian the effects are hard to predict. This means that trying to strategize is hard. It is sort of like saying having a car which is falling apart will prevent you from speeding. It makes it more risky sure but that is not a good motivation to not have something better.

    In the end, it is really STAR which everybody should get behind.


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