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<div class="moz-cite-prefix"><br>
Mike,<br>
<br>
When it comes to Condorcet methods, I think that (up to a point)
some truncation incentive (and so some "vulnerability to<br>
truncation") is somewhere between a good thing and a relatively
small necessary evil ("necessary" to avoid greater evil).<br>
<br>
<blockquote type="cite">
<p dir="ltr">The strategy situation of the methods you listed
isn't as good as Bucklin.</p>
<p dir="ltr">Surely the purpose of a pairwise-count method is to
_improve_ on Bucklin.</p>
</blockquote>
<br>
C: The methods I listed all meet Smith and Bucklin doesn't.
Under Bucklin all voters have such a strong truncation incentive
that<br>
the method is more-or-less strategically equivalent to Approval.<br>
<br>
Under Benham and LV(erw) SME informed strategists have a much
weaker truncation incentive and in the zero-info. case there <br>
is no truncation incentive.<br>
<br>
Given that burial vulnerability is unavoidable in Condorcet
methods, I think that is more democratic if (in this respect)
larger factions<br>
have the advantage over smaller factions.<br>
<br>
43: A<br>
03: A>B<br>
44: B>C (sincere is B or B>A)<br>
10: C<br>
<br>
C>A 54-46, A>B 46-44, B>C 47-10. <br>
<br>
Here A is the sincere CW and supported by the largest of the three
factions of voters, but Winning Votes rewards the buriers by
electing B.<br>
<br>
Benham and LV(erw)SME easily elect A. Smith//Approval
elects C.<br>
<br>
<blockquote type="cite">Smith//Approval shares the great
vulnerability to truncation & burial.</blockquote>
<br>
C: Obviously the supporters of the sincere CW have much less
truncation incentive under Smith//Approval than they do under
Bucklin,<br>
so I wonder what example you have in mind.<br>
<br>
40: A>B<br>
35: B<br>
25: C<br>
<br>
The Condorcet winner is A, but under Bucklin the A supporters'
failure to truncate gives the win to B.<br>
<br>
Chris Benham<br>
<br>
<br>
<br>
On 10/9/2016 7:50 AM, Michael Ossipoff wrote:<br>
</div>
<blockquote
cite="mid:CAOKDY5BHvzUspdaD7ouaqOxuneCsdm1i1J-M4XXCXfDO=Wz4ew@mail.gmail.com"
type="cite">
<p dir="ltr"><br>
On Oct 8, 2016 6:06 AM, "C.Benham" <<a moz-do-not-send="true"
href="mailto:cbenham@adam.com.au">cbenham@adam.com.au</a>>
wrote:<br>
><br>
> Mike,<br>
><br>
> As far as I can tell, for all intents and purposes MAM,
Schulze, River and Smith//MinMax (wv) are all just different
wordings<br>
> of the same method.</p>
<p dir="ltr">No. They sometimes choose different winners.<br>
><br>
> If you think that MAM is better than Shulze, then what
criterion (that we might care about) is met by MAM and not
Shulze?</p>
<p dir="ltr">Sometimes they choose the same, sometimes they don't.</p>
<p dir="ltr">When they don't, the MAM winner is publicly preferred
to the Schulze winner several times more often than vice-versa.</p>
<p dir="ltr">(It seems to me that it might have been something
like 4 to 1, or 5 to 1. Steve Eppley would be the one to ask.)</p>
<p dir="ltr">So: Choose in keeping with public preference, or
contrary to it. Your choice</p>
<p dir="ltr">MAM's brief, natural & obvious definition is the
opposite of the arbitrary definition of Schulze or CSSD.</p>
<p dir="ltr">MAM's definition clearly is the one that doesn't
unnecessarily disregard a defeat. </p>
<p dir="ltr">It disregards a defeat only it's the weakest in a
cycle with defeats for which there _isn't_<br>
justification to disregard them.</p>
<p dir="ltr">And, as I said, it's no surprise when unnecessarily
disregarding defeats results in a winner to whom the public
prefer the MAM winner.<br>
</p>
<p dir="ltr">><br>
> Or perhaps you have some example in mind where you think
the MAM winner is much prettier than the Schulze winner?</p>
<p dir="ltr">Publicly-preferred is prettier.</p>
<p dir="ltr">Minimally disregarding defeats only with obviousl,
strong justification, never unnecessarily disregarding a
defeat--That's prettier.</p>
<p dir="ltr">><br>
><br>
>> MAM's brief definition just says:<br>
>><br>
>> A defeat is affirmed if it isn't the weakest defeat in
a cycle whose other defeats are affirmed.<br>
>><br>
><br>
> C: Is that definition fully adequate? </p>
<p dir="ltr">Yes.</p>
<p dir="ltr">You wrote:</p>
<p dir="ltr">It doesn't tell you where to start.<br>
></p>
<p dir="ltr">It isn't a procedural definition or a
count-instruction. It's a brief recursive definition.</p>
<p dir="ltr">Given a set of rankings, it fully and definitely
specifies a set of affirmed defeats, & a set of not-affirmed
defeats.</p>
<p dir="ltr">...and fully specifies the winner.</p>
<p dir="ltr">For a procedure:</p>
<p dir="ltr">Write down the strongest defeat.</p>
<p dir="ltr">Below it, write down the next strongest defeat.</p>
<p dir="ltr">Below that, write down the next strongest defeat, if
it doesn't cycle with defeats already written down.</p>
<p dir="ltr">Repeat the paragraph before this one, until all the
defeats have been considered as described in that paragraph.</p>
<p dir="ltr">A candidate wins if s/he has no written-down defeats.</p>
<p dir="ltr">(end of count instruction)<br>
</p>
<p dir="ltr">>> So, if it will be rare for them to differ,
does that mean that we should propose the more
complicatedly-worded, elaborately- worded one?<br>
>><br>
>> ...the less obviously, naturally and clearly motivated
& justified one?<br>
>><br>
><br>
> C: Recently you accepted that Winning Votes is at best
"maybe a bit questionable", so why do you think that we should
"propose" either?</p>
<p dir="ltr">(endquote)</p>
<p dir="ltr">I said they might be iffy or questionable. I didn't
say they're ruled out.</p>
<p dir="ltr">For that questionable-ness, you get a chance for much
better strategy.</p>
<p dir="ltr">...at the cost of the possibility of the strategic
mess of the perpetual-burial fiasco.</p>
<p dir="ltr">I'd say that MAM, Smith//MMPO, & plain MMPO are
worth a try.</p>
<p dir="ltr">They should be included in a proposal that lists a
number of suggested methods.</p>
<p dir="ltr">In particular, for an unlimited-rankings method,
Plain MMPO offers the most, for current conditions.</p>
<p dir="ltr">><br>
> If you want a Condorcet method that meets Chicken Dilemma
then I prefer both "Benham" and Losing Votes (erw) Sorted
Margins Elimination.</p>
<p dir="ltr">(endquote)</p>
<p dir="ltr">They're far too vulnerable to truncation &
burial.</p>
<p dir="ltr">In WV & MMPO, truncation just doesn't work. The
CWs still wins.</p>
<p dir="ltr">The strategy situation of the methods you listed
isn't as good as Bucklin.</p>
<p dir="ltr">Surely the purpose of a pairwise-count method is to
_improve_ on Bucklin.</p>
<p dir="ltr">In Bucklin & Approval, the CWs's preferrers can
protect hir win by plumping.</p>
<p dir="ltr">In Benham, Woodall, & Margins-Sorted LV
Elimination, the best they can do is:</p>
<p dir="ltr">Say it's Worst (W), Middle (M), & Favorite (F).</p>
<p dir="ltr">M is the middle CWs.</p>
<p dir="ltr">The M voters could estimate or look up the expected
sizes of the W & F factions. ...& rank one over the
other probabilistically, so that each one's probability of
pair-beating the other is 50%.<br>
</p>
<p dir="ltr">...so that burial has a 50% chance of backfiring.</p>
<p dir="ltr">In Bucklin, WV or MMPO, they need merely to plump.</p>
<p dir="ltr">Or the F voters could rank M alone in 1st place. That
would work in IRV too (nothing else would).</p>
<p dir="ltr">As I said, surely the purpose of a pairwise-count
method is to _improve_ on Bucklin.<br>
</p>
<p dir="ltr">><br>
> If you want a method that (like WV) meets Minimal Defense
then I prefer Forest's "Max Covered Approval" (which would
nearly always be equivalent<br>
> to Smith//Approval, which I also like.)</p>
<p dir="ltr">Smith//Approval shares the great vulnerability to
truncation & burial.</p>
<p dir="ltr">Michael Ossipoff<br>
><br>
> Chris Benham<br>
><br>
><br>
></p>
</blockquote>
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