[EM] MMPO objections (hopefully better posted)

[Michael Ossipoff]

A few more comments:

Why should 2 voters have the power to elect someone bottom-rated by nearly
everyone?

How about because everyone is bottom-rated by at least half of the voters.

...& because it isn't a positional method.

Those 2 voters didn't do it on their own. They had a lot of help from
everyone else.

...because the A voters & the B voters prefer C to eachother's candidate.

Given that, C's win isn't so surprising or outrageous.

Anyway, the example has no plausibility, at all.

Surely the importance of a bad-example depends on its plausibility.

Yes, MMPO doesn't strictly always elect the CW, and I don't like that. It's
a distinct disadvantage. We expect better from a pairwise-count method.

But with sincere voting, & with no indifference, the CWs (sincere CW)
always wins.

For the CW to lose, it's necessary for one of hir pairwise comparisons to
have high turnout, & be relatively nearly tied.   ...& for someone else's
pairwise comparisons to all be very low turnout & hir defeats nearly tied.

Would you give up the best combination of the best strategy properties
because of a funny, but not outrageous result, one that doesn't wrong
anyone, in a thoroughly implausible example?

Michael Ossipoff
On Sep 17, 2016 1:51 PM, "Michael Ossipoff" <email9648742 at gmail.com> wrote:

> ---------- Forwarded message ----------
> From: "Michael Ossipoff" <email9648742 at gmail.com>
> Date: Sep 17, 2016 12:52 PM
> Subject: MMPO objections
> To: <t at gmail.com>
> Cc:
>
> Though NEO, so far, to me at least, seems to show promise, it hasn't been
> thoroughly checked out enough to be a proposal.
>
> But it's different with MMPO. We've heard people's best arguments against
> MMPO, & it can be said to have  already been well-discussed.
>
> No rank method's result will always look right. All will sometimes do
> something ridiculous.
>
> A method optimized for 1 purpose or standard can't do well by other
> standards.
>
> MMPO achieves what it achieves by looking only at pairwise unpreferredness.
>
> It isn't a positional method, & so you can find an example in which it
> does terribly, positionally.
>
> In Kevin's bad-example, it chooses someone twice as bottom-voted as the
> other candidates, & nearly not top-voted at all.
>
> It certainly isn't a positional method
>
> MMPO isn't a pairwise-defeats method. So you can find an example where it
> does terribly by pairwise defeats.
>
> In Kevin's example, it elects the Condorcet loser, who pairwise loses to
> the others by 1000 to 1, if X = 1000.
>
> It certainly isn't a pairwise defeats method.
>
> We've been looking at pairwise defeats methods for so long that we tend,
> maybe subconsciously, to evaluate by pairwise defeats standards.
>
> A "beats-diagram" shows
> an "=" sign between A & B. They have no defeat, but C has one.
>
> But look under that "=" sign. Half the voters bottom-vote A, & the other
> half bottom-end vote B.
>
> Say two groups both despise eachother. Does that mutual despising cancel
> out, making both groups un-despised?
>
> But that's the fallacy that the beats-diagram & its "=" sign allows you to
> believe.
>
> If the A voters voted among themselves, between B & C, they'd choose C.
>
> If the B voters voted among themselves, between A & C, they'd choose C.
>
> C is the compromise preferred by the A voters, & by the C voters, to
> eachother's candidates.
>
> Yes, it's natural to reject a low-favoriteness compromise. Rob Richie
> would be proud.
>
> Of course this bad-example makes that compromise as little top-voted as
> possible.
>
> I've told, here, why the bad-example isn't as bad as you think.
>
> It doesn't look good by standards other than the one by which it achieves
> the elusive goal of MAM-like strategy, without chicken-dilemma.
>
> Distinguish between a harmless election of a low favoriteness compromise,
> a compromise outcome that looks bad to an outside observer vs an actual
> practical problem, one that will routinely
> make strategy problems for voters, and give tangibly (not just
> aesthetically) bad results.
>
> When proposing better voting to a community of jurisdiction, of whatever
> size, offer them a list of methods, telling the objections to each, & their
> answers.   ...& telling the advantages of each.
>
> It would be irresponsible to leave out one with an impressive, unique,
> powerful combination of strategy advantages.
>
> Let the community, jts voters &/or the initiative proposal committee
> choose for themselves. It isn't necessary to make decisions for them.
>
> Michael Ossipoff
>
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