[EM] Oops! MMPO with summed disapprovals as an opposition elects B in ABE. FBC/ABE roundup.

[Jameson Quinn]

2012/1/11 MIKE OSSIPOFF <nkklrp at hotmail.com>

>
> Forest--
>
> The Approval bad-example:
>
> 27: A>B
> 24: B
> 49: C
>
> B's negative score is 49, the number who rank C over B, and also the
> number who don't rank B
>
> C's negative score is 51, the number who rank B over C, and also the
> number who don't rank C
>
> A's negative score is 73, the number who don't rank A
>

> B has the lowest negative score, and wins.
>
> You described a good, diplomatic way to avoid the ABE problem in high-res
> Score Voting. Of course, in public elections,
> that strategy could be implemented probabilistically in Approval.
>
> But that requires information about how many votes C will get.
>
> To me, an FBC/ABE method is one that automatically avoids the
> co-operation/defection problem,
> not requiring predictive information on the part of the A voters.
>
> What kinds of FBC/ABE methods are proposed so far?
>
> Three kinds:
>
> 1. MMPO and MDDTR:
>
> Advantages:
>
> Simple and brief definition. A voters can unilaterally establish coalition
> defeat of C.
>
> Disadvantage:
>
> Criticizable by Mono-Add-Plump or Kevin's MMPO bad-example. Those
> criticisms don't
> describe genuine problems. They don't amount to strategy problems for
> voters. They don't prevent the
> electorate from getting changes that they want. But they could be used by
> opposition to distract
> voters from the important considerations.
>
> 2. Conditional methods such as MMT, GMAT, AOC, MTAOC, MCAOC, AOCBucklin,
> AC, MTAC, MCAC
> and ACBucklin:
>
> Advantages:
>
> Avoids criticisms of #1. Though MMT doesn't meet Mono-Add-Plump, that
> criticism is
> easily answered for MMT. The other conditional methods don't have even
> that criticism, or the
> Kevin's MMPO bad-example criticism eitiher.
>
> These methods are simple, and follow from Plurality and Approval in a
> simple, obvious and natural
> way. Their avoidance of the co-operation/defection problem, too, is
> obvious, simple, natural and
> straightforward, as is its motivation.
>
> These methods can be offered as _options_ in an Approval election. For
> example, all of them other
> than MMT and GMAT can be offered together as options in an Approval
> election.
>
> For the methods other than MMT and GMAT, the conditionality can be
> optional by candidate.
>
> Disadvantages:
>
> One disadvantage: Chris doesn't like them.
>
> Chris doesn't like them because he evidently doesn't like coalition or
> conditionality (though any
> method which, in the ABE, defeats C only if the B voters co-operate is
> conditional too.
>
> The rule-explicitness of the conditional methods' conditionality is what
> makes their avoidance of
> the co-operation/defection problem simple, straightforward and natural.
>
> Chris doesn't like MMT because of its noncompliance with Mono-Add-Plump,
> though that criticism is easily answered.
>
> 3. Methods using Kevin's tied-at-top comparison:
>
> Several have been suggested. No one has claimed that any of them have the
> desired properties.
> They're all speculative.
>
> Advantages:
>
> At least some of them elect A in the standard ABE. In other words, like
> MMPO and MDDTR, the A
> voters can defeat C by unilateral coalition support. They probably avoid
> the criticisms that are
> used against MMPO and MDDTR.
>
> Disadvantages:
>
> Too complicated and wordy of definition.
>
> They're only speculations, as of this time.
>
> I suggest that the conditional methods are the winners.
>

Again, you are leaving out delegated methods; that is, SODA. It's fine if
you think that delegation is unacceptable, or for some other reason still
think conditional methods are best; it is not OK to persistently ignore the
reality that SODA handles FBC and ABE. In fact, for the chicken dilemma /
ABE, SODA clearly gets better results than any of the other methods you've
mentioned; that is, it solves the problem with less real-world risk of
accidentally electing C.

Jameson

>
> Mike Ossipoff
>
>
>
>
>
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>
>
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