<p dir="ltr"><br>
On Sep 29, 2016 11:48 AM, "C.Benham" <<a href="mailto:cbenham@adam.com.au">cbenham@adam.com.au</a>> wrote:<br>
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> Mike,<br>
><br>
> The example we are discussing:<br>
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> 30: A (sincere may be A>B)<br>
> 20: B>A<br>
> 25: C>B<br>
><br>
> You like that Winning Votes and Smith//MMPO elects B.</p>
<p dir="ltr">Yes.</p>
<p dir="ltr">><br>
> On 9/29/2016 12:49 AM, Michael Ossipoff wrote:<br>
><br>
>> Voters will do what it takes, to elect a candidate whom they perceive<br>
as the CWs (sincere CW).<br>
><br>
><br>
> C: How do you know that? </p>
<p dir="ltr">That's typically the best they can get.</p>
<p dir="ltr">(You wrote) :</p>
<p dir="ltr"> Won't they (at least also) try to elect candidates they prefer to their perceived "sincere CW"?</p>
<p dir="ltr">(endquote)</p>
<p dir="ltr">Sure, it's a fair assumption that people who rank want to rank in sincere order for that reason.</p>
<p dir="ltr">I won't approve the expected CWs (CWse) if s/he's bottom-set. (Maybe I'd rank hir in MMPO). So if some others feel similarly, that's an exception to helping the CWse. I don't know how many agree. It would complicate the examples.</p>
<p dir="ltr">> If you are right, then presumably in our example the 3 factions of voters all have different "perceived sincere CWs" because<br>
> they voted for different candidates.</p>
<p dir="ltr">The assumption is that the A voters truncate because they want to make A win instead of the CWse, or that it's lazy or principled truncation.</p>
<p dir="ltr">The C voters rank B over C, helping the CWse.</p>
<p dir="ltr">I think it's a good presumption that all perceive the same CWse, because the same information is available to all.</p>
<p dir="ltr">(I'd said) :</p>
<p dir="ltr">>> Natural, non-strategic, top-cycles are vanishingly rare in political polls. At CIVS (Condorcet Internet Voting Service) I'm not aware of there ever having been a top-cycle for top-finisher.<br>
>><br>
>> So. Most likely there _is_ a CWs (sincere CW).<br>
>><br>
><br>
> C: That isn't rational.</p>
<p dir="ltr">How so?</p>
<p dir="ltr">(You wrote) :</p>
<p dir="ltr"> Presumably a ballot set like our example, with 30 A or 30 A>C is also vanishingly rare.</p>
<p dir="ltr">(endquote)</p>
<p dir="ltr">Yes, if it is a sincere cycle. But otherwise no.</p>
<p dir="ltr">(You wrote) :</p>
<p dir="ltr"> The question isn't how rare top-cycles in general are.<br>
> The question is how reasonable is to assume that the A truncators in this particular example are insincere.<br>
(endquote)</p>
<p dir="ltr">The rarity of sincere top cycles is highly relevant to the matter of this cycle's sincere-ness.</p>
<p dir="ltr">The A voters could prefer B to C, but do principled or strategic truncation.</p>
<p dir="ltr">B would then still be CWs.</p>
<p dir="ltr">(You wrote) :</p>
<p dir="ltr">> In essence an election method should aim to achieve just two things: maximise probable Social Utility and minimise possible voter regret. If fulfilling those aims<br>
> is done without electing some candidate that someone imagines is the "sincere CW", then that isn't a problem.</p>
<p dir="ltr">(endquote)</p>
<p dir="ltr">That's a matter of individual preference. I prefer making easy for those wanting to protect a perceived CWs. You want to maximize SU. Neither goal is wrong.</p>
<p dir="ltr">BTW, if distance in issue-space is measured by city-block distance, then the CWs is the SU maximizer.</p>
<p dir="ltr">...& there's good justification for city block distance.</p>
<p dir="ltr">But SU is of doubtful importance. Greater disutilities are more important to reduce than smaller ones. Is giving a dollar to a millionaire really as good as giving it to a homeless person? (or giving the millionaire some larger amount that has equal utility to him)</p>
<p dir="ltr">> In the example there is no compelling rational reason to assume that any of the ballots are insincere. So there is no "sincere CW".</p>
<p dir="ltr">1.Sincere top cycles are evidently vanishingly rare. </p>
<p dir="ltr">2. It's good to minimize the strategic insincerity needed by someone who wants to protect a perceived CWs.</p>
<p dir="ltr">(I'm not saying that other goals are wrong.)<br></p>
<p dir="ltr">> A, as an uncovered positionally dominant candidate is presumably the highest SU candidate.</p>
<p dir="ltr">A perfectly valid goal. But the CWs is a likely SU maximizer.</p>
<p dir="ltr">(Replying farther down)</p>
<p dir="ltr">(You wrote) :</p>
<p dir="ltr"> (All the Condorcet methods I currently advocate would elect A).<br>
><br>
> So say we elect A. In that case the 25 C>B voters might regret not making their second-choice win (in any Condorcet method) by voting C=B (or B>C or B).<br>
><br>
> But say instead Winning Votes or Smith//MMPO is used and we elect B. In that case the 30 A voters would regret not causing their favourite to win by<br>
> voting A>C.</p>
<p dir="ltr">That wouldn't have worked, if the B voters defensively plumped. The A voters would be taking a big risk.</p>
<p dir="ltr">><br>
> And that clinches the case for any good method that elects A versus any method that elects B with the 30 A voters truncating, and A when they vote A>C.</p>
<p dir="ltr">Depends on one's goal.</p>
<p dir="ltr">><br>
> Approval Sorted Margins isn't as bad because under it if the A supporters vote A>C it results in C winning. <br>
(endquote)</p>
<p dir="ltr">If B voters plump, wv does the same.</p>
<p dir="ltr">>Also it meets mono-switch->plump and of course<br>
> (since above-bottom ranking is interpreted as approval) has some truncation incentive.</p>
<p dir="ltr">ASM is worth checking out. A disadvantage is that principled truncation of the CWs is more likely to defeat the CWs & elect someone whom the truncators dislike more.</p>
<p dir="ltr">Michael Ossipoff<br>
> Chris Benham<br>
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