Re: [EM] [CES #9004] Before Voting Methods and Criteria: Outcome Design Goals (long)
Benjamin: You are right to point out that we should have some discussion of basic principles to underly our discussion of specific systems. Here are my own views: 1. There is no single easy philosophical answer to these questions. There will always be those who, like Clay, would rather grab the quick self-consistent certainty of interpersonally-summable utilities; and it is true that this point of view offers many advantages (for instance, immediate immunity to probabilistic or Arrovian money-pump arguments); but it also has serious philosophical critiques. There is a continuum of possible self-consistent answers to the breadth-versus-depth question that runs from maximin to summed-utility to maximax, and if you allow certain kinds of status-quo bias, the possibilities are even broader. 2. However, for practical terms, we are not likely to get a better metric for voting systems than total utility. A maximin metric would philosophically give veto power to a single voter; an intermediate metric would probably be equivalent to summed-utility if you rescale utility by some monotic function; and any metric involving status quo bias extrinsic to the voters themselves, is a horrible compass for system design. So while I don't share Clay's easy certainty about the impeccable solidity of the philosophical foundations here, I do agree with him that this is the best single measure of outcome quality. 3. That doesn't make things easy, though. For instance, for a given set of ballots, the Score result is usually (though not always!) the best way to use the information given to try to maximize the underlying utilities. But since voters will almost certainly vote differently under different systems, that does not mean that Score is the best way to ensure the best result from a pre-balloting point of view. Or another instance: system A could give better results, but system B might be more likely to be implemented and thus offer more expected value over status quo C. Jameson 2013/6/30 Benjamin Grant b...@4efix.com I’ve been coming at understanding better the options and choices, merits and flaws of various approaches to holding votes – mostly with the kind (and sometimes not-so-kind) help of the people on this list. ** ** However, a (I assume) basic thought occurred to me, which may be so obvious no one need ever discuss it, but I want to double check my thinking on some of this. ** ** The rest of this post will NOT be concerned with any one particular voting method or criteria. Instead I will be comparing different scenarios of voter preference with thoughts about who “should” win. If I am not making sense quite yet, come along and hopefully it will make more sense in practice. If not, you can ask me questions or delete the post. ** ** Let’s assume that we have a magical gift – a super power, if you will. We can know exactly what each voter thinks about each candidate. Now, because this comes from magic, it cannot unfortunately be used as a part of the election process, but it will be useful for our examination of attitudes of the voters. ** ** So as we turn our power on a random voter, we can pick (on a scale of 0 to 100) how they feel about each candidate. A 0, in this case, indicates that the voter is absolutely against the candidate winning the election, and will vote however he must to stop that from happening, whereas a 100 indicates the reverse: that the voter is absolutely for this candidate’s victory, and will give it everything he can at the ballot box. 50 indicates a sort of “meh” reaction – doesn’t hate them, doesn’t love them – or possibly the voter has some aspects of the candidate he really likes, but some other aspects that he is less than thrilled with. ** ** So, using this power, we can know absolutely on a scale of 0 to 100 what each voter thinks of each candidate. Using that knowledge, we ought to be able to say who “should” win – which I will return to in just a moment.*** * ** ** First, each candidate’s support by the voters can be noted on a graph, with the X axis denoting the scale of 0-100 Favorability, and the Y axis denoting the percentage of voters who hold that exact opinion. ** ** So, for example, on a graph like this, you might find that 12% rate a certain candidate at 0F – they *hate* this guy. Another 14% may rate this candidate at 100F – these are his loyal base. Most people fall somewhere in between. ** ** To keep things simple, I’m going to talk about candidates as if their voters clump at certain points, instead of spreading more fuzzily. I think the core questions become no less valid and no less worth thought. ** ** I am going to posit a series of two candidate comparisons, and ask who “should” win. The point here is to ignore the methods for a bit, and just see what our gut says, given the absolutely magically accurate information we have about the voter’s
Re: [EM] [CES #9004] Before Voting Methods and Criteria: Outcome Design Goals (long)
At 11:03 AM 7/1/2013, Jameson Quinn wrote: Benjamin: You are right to point out that we should have some discussion of basic principles to underly our discussion of specific systems. Here are my own views: 1. There is no single easy philosophical answer to these questions. There will always be those who, like Clay, would rather grab the quick self-consistent certainty of interpersonally-summable utilities; and it is true that this point of view offers many advantages (for instance, immediate immunity to probabilistic or Arrovian money-pump arguments); but it also has serious philosophical critiques. There is a continuum of possible self-consistent answers to the breadth-versus-depth question that runs from maximin to summed-utility to maximax, and if you allow certain kinds of status-quo bias, the possibilities are even broader. My take on this is that the hypothesis of interpersonally-summable utiliities is useful but not the truth. What the Bayesian Regret studies do is to show how a voting system performs *if* there are summable utilities. With proper design, those simulated utilities can be quire reasonable. A voting system that peforms poorly with *known utilities* is not likely to perform well with unknown ones. So BR studies are the best measure we have, so far, for assessing voting system performance. Given this, Range voting would seem to be an ideal voting system, because, on the fact, it sums those utilities. In fact, there is a translation process between internal utilities and actual votes that introduce distortion into the system. The first is normalization, where the realistic options are mapped to the full vote scale. If there is simple normalization only, then voters would essentially disempower themselves if they have a very strong preference, a *must have* or *must defeat.* So there is what I've called magnification, where voters would stretch or compress the voting preference strengths (the differences between two voted values) in order to match assessments of relative value as adjusted for election probabilities. All this means that the actual range vote sum is not necessarily the actual social utility maximizer. In particular, if the voters don't have good data on election probabilities, and, more than that, have *incorrect information*, they may vote foolishly. This problem is handled if the system uses repeated elections, because, after the first election, they should have much better information about what is probable, if the voting system does allow the disclosure of that information. 2. However, for practical terms, we are not likely to get a better metric for voting systems than total utility. A maximin metric would philosophically give veto power to a single voter; an intermediate metric would probably be equivalent to summed-utility if you rescale utility by some monotic function; and any metric involving status quo bias extrinsic to the voters themselves, is a horrible compass for system design. So while I don't share Clay's easy certainty about the impeccable solidity of the philosophical foundations here, I do agree with him that this is the best single measure of outcome quality. And I agree on that as well. This leaves two issues: 1. The practicality of implementation. 2. Majority consent. The latter has often been seriously neglected. IRV was sold on a claim that it would find majorities. Essentially, FairVote lied, or allowed people, in some cases, to be decieved by naive expectations. We don't know that FairVote *actually corrupted the committee that wrote the voter information booklet* that led voters to approve Ranked Choice Voting in San Francisco, but we can be quite sure that FairVote took no steps to correct it, and what was said that was just plain wrong has been said by them in many places, though the gradually became more careful. They now say this majority thing in such a way that naive voters won't understand the difference, but if you call them on it, what they say is defensible. It's just misleading, not directly a lie. The biggest problem in the way of implementing Range is lack of any test for majority consent. Range (Score) is a *plurality method.* With all the anti-Plurality hype, that's totally overlooked. All that has happened with Range is that fractional votes are allowed. While, in theory, it can take an endless series of repeated elections to find a majority, the probability of that is vanishingly low. People *do* make the necessary adjustments, unless the majority *does not want to complete*, in which case that is the majority decision. Who is to say that this is wrong? However, my sense is that a two-round system with intelligent choice of nominations for the second round can find a *true majority* almost all the time. And when it fails, it would be close enough that the value of continuing the process would be less than the cost of continuing it. 3. That
