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<pre><br><i><br></i>Kristofer:<br><br>I'd said:<br><br><i></i>><i> You haven't shown that Kevin's MMPO bad-example is a problem in that sense.<br></i><br>You replied:<br><br>I think my primary objection is that it doesn't make sense. <br><br>[endquote]<br><br>Quite so. It doesn't make sense when compared to the Plurality results that we're<br>familiar with. MMPO differs drastically from Plurality, and can give results that<br>are disturbing if we expect Plurality-like results. <br><br>That's why the conditional methods might be the most feasible public proposals <br>for achieving FBC/ABE. They're solidly based on, and follow naturally from,<br>Approval and Plurality.<br><br>You continued:<br><br>Perhaps that <br>is aesthetic, perhaps it is based on logic. <br><br>[endquote]<br><br>...but it's regrettable if we have to forgo MMPO's _practical_ advantages because of that.<br><br>Yes, MMPO has a random-fill incentive and a burying incentive, but burial won't threaten<br>a set of candidates mutually AERLO-protected by a majority of the voters.<br><br>Of course practicality has to also include the matter of what's practical to propose<br>to people.<br><br>You continued:<br><br>But, as I'll say below, <br>Plurality (the criterion) is much more than Plurality (the method)<br><br>[endquote]<br><br>Sure. I'm just saying that, because people are accustomed to Plurality and its results,<br>they don't like it when a method does something dramatically different from what Plurality<br>would do. But favoriteness isn't everything.<br><br>Of course the Plurality Criterion makes sense as an aesthetic desideratum. But we have to decide<br>what is most important. <br><br>But if Kevin's bad-example, and Mono-Add-Plump are a problem, I think some or most of the <br>conditional methods that comply with those criteria would be publicly acceptable. In fact,<br>they're the proposals that I'd start with, for that reason.<br><br>You continued:<br><br>; and <br>I think, though I am of course not certain of this, that the vast <br>majority of people would find something wrong with how MMPO resolves the <br>situation.<br><br>[endquote]<br><br>Probably. And the opposition to an MMPO enactment proposal would make sure everyone received<br>a copy of Kevin's MMPO bad-example, probably as a doorknob-hanger-brochure, and in the<br>broadcast media.<br><br>You continued:<br><br>Or to try to put what I think (and how I think people would react) into <br>more direct terms: this would be like "everybody but Bush" voters and <br>"everybody but Gore" voters (A and B plumpers respectively) wake up and <br>find that, because a single voter voted some obscure candidate (say <br>Hagelin) equal to Gore, and another voter voted the same obscure <br>candidate equal to Bush, that obscure candidate won.<br><br>[endquote]<br><br>Most likely, yes, they wouldn't like it, then, or when the opposition <br>publicized the possibility during the enactment campaign.<br><br>I'm interested in avoiding the worst strategy problems, but others are influenced by<br>other things, and there's a good chance that the public could be turned against MMPO <br>when Kevin's bad-example is publicized.<br><br>You continued:<br><br>Sure, you could say that the everybody-but-Bush and everybody-but-Gore <br>voters should have clarified, in their ballots, that they do prefer Gore <br>and Bush (respectively) to Hagelin - but I think it would seem wrong to <br>the voters that they would have to do so, and that the method would not <br>just degrade gracefully if they did vote "everybody but Bush/Gore" right <br>out.<br><br>[endquote]<br><br>Yes that's likely so.<br><br>The methods (MMPO & MDDTR) that avoid the ABE problem by counting pairwise<br>opposition have advantages, but could act in ways that could be unexpected<br>and seem outrageous to people familiar with the Plurality method's results.<br>The opposition in an enactment campaign would make sure that everyone heard<br>about those kind of possible results.<br><br>Sure, the noncompliances with the Plurality Criterion are more than just an<br>election of a Plurality nonwinner. And people's accustomed-ness to the Plurality<br>method can make them outraged when they see the similar, but bigger and more unexpected,<br>result when a method doesn't comply with the Plurality Criterion.<br><br><br>I'd said:<br><br>><i> Someone on this list was terribly bothered by the mutuality-requirement, referring to it as "sordid".<br></i>><i><br></i>><i> He'll think this is terribly sordid, but if a faction of voters want coalition support for their<br></i>><i> candidate, why would it be important to them that they not support that coalition?<br></i>><i><br></i>><i> They want to not help the people whose help they need?<br></i>><i><br></i>><i> Oh what a cruel strategy-need to burden someone with! :-)<br></i><br>(I want to emphasize that most of the conditional methods, including most of the<br>ones based on mutual coalition, meet Mono-Add-Plump. When discussing conditional methods<br>that fail Mono-Add-Plump, we're only talking about MMT.)<br><br>You replied:<br><br>When I read this, I recognized something that may explain others' <br>disagreement about the relative value of these criteria, and <br>mono-add-plump in particular.<br><br>In my mind, a preference ordering is (or should be) disconnected from <br>the method to which it is fed. In other words, a honest ranked ballot is <br>an expression of the wishes or preferences of the voter independent of <br>the voting system. In essence, he is saying "if it was up to me, I'd <br>have A, but if I couldn't have A, I would have B" and so on.<br><br>[endquote]<br><br>That's the (unattainable) ideal. Gibbard & Satterthwaite showed that it doesn't<br>work like that. One can just rank sincerely if one wants to, but one cannot<br>expect to optimize one's outcome thereby.<br><br>You continued:<br><br>In that light, a criterion-based approach becomes much more sensible. <br><br>[endquote]<br><br>I've always liked criteria. FBC and Co-operation/Defection (CD) are criteria, for<br>example.<br><br>You continued:<br><br>If <br>an election method is a black box that takes preferences as inputs and <br>tries to "mechanically mediate" between the preferences to find the best <br>social outcome<br><br>[endquote]<br><br>"Best social outcome" leaves a lot of room for disagreement. To me, the<br>method with the best social consequences is the one that best avoids<br>causing strategy problems that prevent an electorate from getting what they<br>most want. Favorite-burial and the co-operation/defection problem have particularly<br>detrimental social consequences.<br><br>You continued:<br><br>, then it doesn't matter what happens inside the black <br>box. What matters is the relation between the outputs and the inputs. If <br>a method fails mono-add-plump, that means that when someone says "As for <br>me, I prefer A to everybody else", then the method uses that preference <br>to decide that "oh, A wasn't that good a choice after all". That may <br>happen because of mutuality requirements, or because of some unintuitive <br>internal logic, but the outcome changes in a way that is detrimental to <br>the voter who made the outcome change in the first place, and this voter <br>doesn't know anything about mutuality or coalition preferences or the <br>internals of the method when voting honestly.<br><br>[endquote]<br><br>In the examples that Chris posted, the plumping voters had no<br>strategic reason to do so. Plumping was obvious bad strategy in that<br>MMT election.<br><br>Yes it would be nice if everyone only needed to rank sincerely. <br><br>Maybe that ideal could be closely approached by AOCBucklin with AERLO, or<br>by MMPO with AERLO. <br><br>You continued:<br><br>If others have this view of preference orderings as well, that could <br>explain why they don't like a method failing mono-add-plump, and why an <br>explanation of how the method works doesn't change their minds.<br><br>[endquote]<br><br>But how realistic is it to expect pure, naive sincere voting to always<br>be optimal?<br><br>You continued:<br><br>Obviously, no method can pass every criterion, but mono-add-plump is <br>relatively "cheap" in that most methods out there pass it.<br><br>Most of the FBC/ABE methods that I like pass Mono-Add-Plump.<br><br>MDDTR and MMT are the notable exceptions. In the case of MMT, the folly<br>of the plumpers is easily shown.<br><br>Yes, MMT is suboptimal because, as you say, it doesn't avoid an avoidable<br>problem. MMPO, GMAT, AOC, MTAOC, MCAOC and AOCBucklin avoid it.<br><br>But what if MMT were the only proposable FBC/ABE method. As I said, I don't<br>think it is. I think that AOC, MTAOC and MCAOC are fully proposable.<br><br>It's necessary to do polling to find out which FBC/ABE methods are the <br>most acceptable. <br><br>Only that will tell us whether people will reject MMT because of Mono-Add-Plump.<br>...if people will think that the coalition-rejecting plumpers are unfairly<br>treated in MMT.<br><br>And I repeat that the other conditional methods, other than MMT, don't fail<br>Mono-Add-Plump.<br><br>Mike Ossipoff<br><br><br><br><br><br><br></pre> </div></body>
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