# [EM] MMPO objections (hopefully better posted)

Michael Ossipoff email9648742 at gmail.com
Wed Sep 21 16:37:20 PDT 2016

```I didn't say that C is the best winner. But you said it's an "outrage".

Half the voters saying C is just as good as A, and the other half saying C
is just as good as B...Surely that should dampen your outrage.

The A voters could have voted A>B>C, had they cared.

No surprise that it doesn't give the results of a positional method or a
pairwise-defeats method. Best? No, but your outrage seems a bit exaggerated.

Michael Ossipoff
On Sep 20, 2016 5:29 PM, "C.Benham" <cbenham at adam.com.au> wrote:

> Mike,
>
> The  MinMax Pairwise Opposition (MMPO)  "bad example" we are talking about:
>
> x: A
> 1: A=C
> 1: B=C
> x: B
>
> x  = any number greater than 1.   MMPO elects C.
>
>
> On 9/19/2016 4:15 AM, Michael Ossipoff wrote:
>
> 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 each other's candidate.
>
>
> C: There's no evidence on the ballots for that assertion.
>
> Surely the importance of a bad-example depends on its plausibility.
>
>
> C: Not when it's that bad.  And not even when it's merely very bad in such
> a simple example.  It is more understandable
> and perhaps forgiveable for an algorithm to become "confused" in a
> complicated example (with say, lots of candidates
> and cycles within cycles).
>
> 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?
>
>
> C: I don't agree with most of the premises in that question.  Other
> methods meet FBC and CD. What's so good about Later-no-Harm with a
> random-fill incentive?
>
> The result is completely outrageous and absurd.
>
> The correct result is an A=B tie.  All but 2 of the voters were wronged,
> because their favourites should have a 50%  probability of winning.
>
> Chris Benham
>
>
>
>
> On 9/19/2016 4:15 AM, Michael Ossipoff wrote:
>
>
> 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
>>
>> When proposing better voting to a community of jurisdiction, of whatever
>> size, offer them a list of methods, telling the objections to each, & their
>>
>> 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
>>
>
>
> ----
> Election-Methods mailing list - see http://electorama.com/em for list info
>
>
>
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2016.0.7797 / Virus Database: 4656/13038 - Release Date: 09/18/16
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.electorama.com/pipermail/election-methods-electorama.com/attachments/20160921/7e634735/attachment.htm>
```