[EM] MMPO and FBC. Votes-only criteria.

Jameson Quinn jameson.quinn at gmail.com
Fri Oct 28 09:31:29 PDT 2011


2011/10/28 MIKE OSSIPOFF <nkklrp at hotmail.com>

>
> (Sorry to change the subject line, but this one is much easier to write.)
>
>
> Kevin wrote:
>
> Mike's method is Condorcet//MMPO//Condorcet//MMPO//etc.
>
> [unquote]
>
> No. I initially defined such a method. Then I said that I propose only
>
> MMPO (applied to its own ties), because FBC is more important than Condorcet's
> Criterion. I said that, as I define MMPO, it _doesn't_ include a CW search, because
> I want FBC compliance.
>
> I propose MMPO//MMPO//MMPO...
>
> Kevin wrote:
>
> However, even if Mike's method were just MMPO//MMPO//MMPO//etc I
> still highly doubt that would satisfy FBC, because the candidate
> eliminations and recalculations make it unclear that votes will work
>
> as expected. I don't know how to say this much more clearly than that.
> But let me ask you, how many FBC-satisfying methods involve eliminating
> candidates and then recalculating scores once those candidates are
>
> removed? Not a one.
>
>
> [unquote]
>
> I mentioned and answered that argument yesterday on EM.
>
> I'd say it again today, but I don't have long on the computer today. I refer you to
> my posting yesterday.
>
> Kevin wrote:
>
> Hypothetically, off the top of my head, lowering your true favorite
> could remove him from a three-way score tie which then (as a two-way)
> is resolved for one of your "other" favorites, whereas the three-way
>
> contest is resolved for a disliked candidate.
>
> If a compromise (C) could win in a tie, but your favorite (F) couldn't, that must
> be because C has lower maximum pairwise opposition (MPO) than F.
>
> But, if that's so, then why do you need to vote C over F, to get C into a tie?
>
> I'll be visiting, staying with, relatives this weekend, and I may not get much, if any,
> time on computers this weekend.  For instance, today there's only time for this one posting.
>
> Quinn said that criteria cannot mention sincere preferences.
>
>
What I meant was, if a criterion says system X must give result Y for
ballots Z and sincere preferences Q, then it also says that X must give Y
for Z and R. As long as there is some Q for which (Q,Z) meets the criterion,
then Z meets the criterion for any preferences. This is just what a voting
system is; if it gives Y for (Q,Z), it gives Y for (Q,R), unless it can read
minds.

JQ
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.electorama.com/pipermail/election-methods-electorama.com/attachments/20111028/9b339e34/attachment-0004.htm>


More information about the Election-Methods mailing list