Hi folks, I thought y'all might be interested in this report from Brookings: https://www.brookings.edu/articles/the-future-of-the-instant-runoff-election-reform/ I'm curious what y'all think of the report. Rob

On 2025-05-20 00:30, Rob Lanphier via Election-Methods wrote: > Hi folks, > > I thought y'all might be interested in this report from Brookings: > https://www.brookings.edu/articles/the-future-of-the-instant-runoff-election-reform/ <https://www.brookings.edu/articles/the-future-of-the-instant-runoff-election-reform/> > > I'm curious what y'all think of the report. Parts of what it's reporting seem quite understandable: that parties that are in power don't like having their power challenged by new election methods that don't share the flaws that gave them extra power to begin with, for instance. It also seems quite understandable that parties that were "snubbed" by IRV (e.g. by center squeeze) would feel that the method is stacked against them, even if IRV is pretty indiscriminate in what direction (left or right) it denies CWs victory. What surprised me are the arguments *against* IRV: that it violates OMOV, that it's complex, and that it's a foreign state invention. It's true that IRV's outcome can be chaotic (just take a look at Yee diagrams). And it's also true that determining why IRV picked the winner it did can be hard to do. It can also be difficult to come up with a justification for why IRV picked the candidate it did, besides "that's the algorithm, and that's the result". But each voter still has one ranked vote each, so in that respect it respects OMOV. As a measure of quality, IRV is complex: the chaos means that a candidate may go from unacceptable to acceptable even though there's no obvious reason. But I've been led to think that *as an algorithm*, its simplicity (tally and eliminate, repeat) is one of its stronger points. Maybe that's wrong? Or maybe the voters are reacting to the opacity of the outcome, not the process? If it's the latter, then at least theoretically, something like Copeland//Plurality or Copeland//TTR could actually be at an advantage. On the other hand, if the voters are feeling there's a violation of OMOV because the ranked ballot allows people to vote for multiple candidates, then all ranked methods are going to have a problem, and something like Approval is going to have an even bigger one, since the ballot format makes it look like each voter gets as many votes as candidates they approve.[1] The "it's a California method" objection is reasonable if what it really means is "we didn't ask for it, outside sponsors are instead just rolling up and ramming it down our throats". But less so if it's a not-invented-here objection - after all, states that use FPTP use the same FPTP, not their own slightly different method. (On an aside, I was surprised at the "open primaries" joke, which to me seems pretty bad taste, in how it bundles things that have nothing to do with each other. But I guess that's the point: that it's shorthand for "you already agree with me about other things, now agree with me and oppose open primaries".) Finally, about the indication that IRV may be leading to some moderation: I'm reminded of a discussion on Discord about how the Australian two-party system might be weakening. While top-two and IRV are both subject to center-squeeze[2] and Condorcet methods aren't, both TTR and IRV have less of it than Plurality does. The recent Romanian election is a good example. To attempt to treat this more mathematically, in the Left-Center-Right election: 51-x: L>C>R 39-x: R>C>L 2x: C>R>L C wins in FPTP when x > 17, in IRV when x > 13, and in Condorcet when x > 6. So in that respect FPTP's center squeeze is the worst, IRV has some (relative to FPTP), and Condorcet has little. So if new party formation depends on how safe it is to vote for candidates closer to the center, then above some threshold of center-squeeze, the method so strongly deters new entry that you get two-party rule. Below this threshold you would get a tendency for new entrants to appear, but they would grow more slowly the closer to the threshold the method resides. It may thus be that IRV does reduce polarization compared to FPTP. And it's possible that such reduction of polarization might lead to more competition inside parties and growth of third parties, particularly if the Australian results are indications of a robust trend. However, even if it is, it took Australia a long way to get there - and that's despite their other chamber using STV, a proportional multiwinner method. Is IRV's moderating effect sufficiently strong to stop what's going on with US polarization? I don't know. But better methods would produce a stronger effect. (It's also possible that center squeeze isn't the only property that matters when it comes to make entry easier for new parties and candidates. My main point is more that center-squeeze can be considered a sliding scale, not just "this has it" vs "this doesn't have it".) -km [1] There are ways to improve on this first impression, but my interactions with certain cardinalists have left me disinclined to elaborate. [2] First impressions would suggest that top-two has a stronger center squeeze than IRV when there are more than three candidates. But this is complicated by the game nature of top-two runoff, where voters can change their mind between rounds.