# [EM] MMPO

Michael Ossipoff email9648742 at gmail.com
Mon Oct 3 13:39:41 PDT 2016

```Yes, now that you mention it, 0-10 or 0-9 Score probably has enough
resolution for the anti-defection fractional-vote strategy.

But, for amicable factions to effectively fully help eachother, while still
ensuring that the bigger faction outpolls the other, it has to be possible
to give a near-unity fraction of a vote.

Michael Ossipoff
On Oct 2, 2016 4:26 PM, "Forest Simmons" <fsimmons at pcc.edu> wrote:

> Michael,
>
> You have a good memory.
>
> Zero to ten might be enough resolution for this technique to work for
> typical levels of information.
>
> Here's another criterion idea for use with Score style ballots:
>
> We could say that candidate X strongly covers candidate Y iff X pairwise
> beats every candidate that Y beats including the virtual candidates (if
> any) that Y beats.
>
> In particular, if Y beats a certain score level by having its median score
> higher than that level, then so should X.
>
> Forest
>
> On Sat, Oct 1, 2016 at 3:16 PM, Michael Ossipoff <email9648742 at gmail.com>
> wrote:
>
>> Yes, avoiding the Plurality criticism could be worth requiring 1/8 of the
>> A voters to truncate B.
>>
>> There could be an agreement between A & B voters, to rank eachother's
>> candidate with 7/8 probability.
>>
>> "Flip a coin 4 times. If it comes down the same way every time, then
>> don't rank them."
>>
>> That reminds me of the Srategic-Fractional-Support anti-defection
>> strategy-suggestion that you made some time ago, & which I've been
>>
>> It's for methods without built-in chicken-dilemma protection, such as
>> Approval.
>>
>> In one version, faction A could try to probabilistically give  faction B
>> just enough votes to make B win if the B faction is bigger than the A
>> faction believes itself to be.
>>
>> Sure, it's a guess, but the A faction's guess is as good as the B
>> faction's guess. They both have access to the same predictive information.
>>
>> So the fact that the  A faction is trying that should deter defection by
>> the B faction.
>>
>> It, too, could be done probabilistically, but it's one reason why I like
>> 0 to 99 or 0 to 999 Score voting.
>>
>> Also, in Approval, amicable factions could probabilistically give
>> eachother's candidate some near-unity fraction of an approval. They're
>> effectively fully helping eachother, but the bigger faction will
>> automatically outpoll the other.
>>
>> Michael Ossipoff
>>
>> On Oct 1, 2016 12:09 PM, "Forest Simmons" <fsimmons at pcc.edu> wrote:
>> >
>> > Here's an idea for fixing MMPO's lack of  Plurality compliabnce:
>> >
>> > Include the opposition of the Implicit Approval Cutoff Candidate, the
>> virtual candidate on the truncation boundary.
>> >
>> > Example:
>> >
>> > 40 A
>> > 10 C>A
>> > 10 C>B
>> > 40 B
>> >
>> > In regular MMPO, the max opposition to C is 40.  But when the number of
>> ballots on which C is truncated is counted among the oppositions, the max
>> opposition becomes 80.  Thus Plurality is rescued.
>> >
>> > How about the Chicken problem?
>> >
>> > Consider
>> >
>> > 49 C
>> > 3 A  (sincere A>B)
>> > 24 A>B
>> > 24 B (sincere B>A)
>> >
>> > Regular MMPO gives A the win contrary to Plurality.
>> > Taking the truncation opposition into account we have max oppositions
>> for A, B, and C, respectively, as  73, 52, and 51.  Candidate C wins,
>> punishing B's defection.  This only required three of the A supporters to
>> truncate B.
>> >
>> > Unfortunately, even this new version of MMPO fails Condorcet Loser and
>> Clone Winner.
>> >
>> > ----
>> > Election-Methods mailing list - see http://electorama.com/em for list
>> info
>> >
>>
>>
>
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