[EM] Bucklin/IRV hybrid? Motivated by MSV strategy

Tue Nov 1 09:56:44 PDT 2016

(Replying farther down)

On Oct 31, 2016 11:06 PM, "C.Benham" <cbenham at adam.com.au> wrote:
>
> On 10/31/2016 7:48 AM, Michael Ossipoff wrote:
>
>> Of course at EM we discuss two completely separate and different method
proposal choices:
>>
>> 1. Proposals to electorates who have only had Plurality.
>>
>> 2. Later proposals to replace one better voting system with another.
>>
>> If we're talking about #1, then there are only a few to choose from:
>>
>> Approval, Score, and Bucklin.
>
>
> Mike,
>
> A short time ago you were in favour of CD methods (and even crafted the
criterion) and said that your
> favourite method is ICT  (aka 3-slot TTR, Top Ratings).

...as a later improvement.

But I recognized that a first reform for people used to Plurality would
have to be something simple, & precedented.

I only suggested 3-Slot ICT as a later refinement.

I still value CD. But I've often said that the Chicken-Dilemma is a
nuisance, rather than a problem, & that CD is a valuable luxury. ...& that
Approval is very acceptable.

I still like 3-Slot ICT, but it has a few drawbacks:

* It isn't as briefly & simply defined as MMPO.

* when you demote B to middle, you're leaving hir with no protection from
burial, or even from innocent truncation.

Besides, activists & organizations want rankings. Some overcompromisers &
rivals likely would do better with rankings.

Regardless of merit, rankings might be psychologically desirable.

>
> So what happened to it?

Answered above.

You wrote:

You even seemed ready to tolerate the non-FBC  CD methods Benham and IRV.

(endquote)

I recognized even then that they had problems for current conditions.

Yes, I used to like them for the Green scenario. I was saying that it's OK
to ignore voters who aren't in a mutual-majority. I no longer feel that way.

IRV & it's derivatives create a confrontational situation & mood when they
make you choose between ranking Compromise over Favorite, or withholding
help from Compromise & letting hir lose.

>
>
>> For #2, it really takes something with a lot of valuable &
otherwise-unobtainable properties, to justify replacing Approval, Score or
Bucklin with it.
>>
>> I suggest that only Plain MMPO qualifies.
>
>
> Say you ask people who are used to and/or like any of  Approval, Score,
Bucklin,  or  plurality (aka FPP) or Top-Two Runoff or IRV or Benham:
>
> (a) Would you accept a method that in a 3-candidate election with 20
million voters can elect a candidate that is voted above equal-bottom
> on only two ballots?
>
> x: A
> 1: C=A
> 1: C=B
> x: B
>
> x = any number greater than 1.   MMPO  elects C.
>
> (b) Do you think it is fair and sensible that a voter who is only
interested in getting their favourite elected can increase the chance of
that
> happening by fully ranking (below top) all the other candidates at
random?

(endquote)

All along, I've been saying that I'd disclose those criticisms, & answer
them. My answers would be the ones that I've posted.

>
> What response do you think you will get?

I don't know. It would only be .mentioned as a possibility. At that future
time when new methods are being considered, as a refinement, people should
be offered a choice of the best combination of valuable strategic
properties, vs a more conservative effort to avoid "could look bad".

Maybe people won't like or want MMPO. Fine. Then I'll recommend that they
keep Approval, Score or Bucklin.

(You wrote):

> I don't live in the US, but I would think that most people wouldn't even
believe that question (a) is serious, and that anyone who tries to
> tell them that that example only "looks bad" would blow their credibility.

Have I ever seemed worried about that?

"Could look bad" isn't important compared to practical strategy properties.

We discussed the matter of whether anyone is seriously wronged in the bad
example.

Michael Ossipoff

>
> Chris Benham
>
>
>
>
>> Jameson--
>>
>>
>> On Sat, Oct 29, 2016 at 11:16 AM, Jameson Quinn <jameson.quinn at gmail.com>
wrote:
>>>
>>>
>>> ....Here's my "ideal characteristics" for a political single-winner
election system, more or less in descending order of importance:
>>> FBC
>>
>>
>> Yes, I consider FBC to be #!.
>>
>>>
>>>
>>> Handles center squeeze (ie, some form of weakened Condorcet guarantee
that's compatible with FBC)
>>
>> But maybe the goal of electing the CWs unnecessarily complicates
votiing. Maybe someday, there won't be a bottom set, for most voters, and,
with honest elections & honest, open media, it will be clear who's the CWs.
But now, Approval's best strategy doesn't require that. Brams pointed out
that Approval's results can be better than the CWs.
>>
>> But, when it's desirable to elect the CWs, and it isn't obvious who's
the CWs, then the wv methods, and methods with wv-like strategy (such as
MMPO), are the methods that make it easiest to protect the CWs.
>>
>> Also, it should be noted that you can't be sure how often there will be
a CWs, under different and better conditions.
>>
>>>
>>>
>>> Relatively simple to explain
>>
>>
>> Approval & Score are easy to explain. I've had conversations in which
only Approval & Score were accepted as being plain & un-elaborate enough to
be acceptable..
>>
>> You know that SARA & XA are complicated and not easy to explain. I've
tried explaining them.
>>
>> MMPO?:
>>
>> "The winner is the candidate who has fewest people voting someone else
over hir."
>>
>> {...some same other candidate)
>>>
>>>
>>> Minimal strategic burden
>>
>>
>> We often hear it said that Approval has a large strategic burden, but,
for most people, with our current candidate-lineup, there's nothing
difficult about it: Approve (only) the progressive candidates. That's
optimal for most people.
>>
>> And if the time comes when, for most people, there isn't a bottom-set,
then that will be a happy circumstance, in which it doesn't matter terribly
anyway, which candidate wins.
>>
>> In such conditions, with honest elections and honest, open media, it
will likely be pretty obvious who's the CWs, and, in the absence of
tep-set/bottom-set, the best strategy will be to just approve down to the
CWs.
>>
>> And, if there were no bottom-set, and if it happened that it _wasn't_
clear who the CWs was, and it was 0-info, then it would just be a matter of
approving down to the expected winning merit-level. Maybe, under those
conditions, that would be the candidate-mean.  Or maybe (as now)  the
estimated mean merit of what voters want (which can be estimated by the
candidates' merit-midrange, if the election is 1D.  ....but it might not
remain 1D under different and better conditions).
>>
>> ..but I repeat that, with only your former top-set remaining as winnable
candidates, it won't make as much difference which one wins anyway.
>>
>> People often consider Approval voting more difficult than it is.
>>
>>
>>>
>>> Summable (ideally O(N), no worse than O(N²) in practice, though I might
accept some special pleading for the use of prior polling to reduce to
O(N²).)
>>> Handles CD, or at least, CD offensive strategies don't in practice mess
up the center squeeze properties.
>>
>>
>> MMPO meets Weak CD.
>>
>>>
>>>
>>> Some arguable track record
>>
>>
>> Of course at EM we discuss two completely separate and different method
proposal choices:
>>
>> 1. Proposals to electorates who have only had Plurality.
>>
>> 2. Later proposals to replace one better voting system with another.
>>
>> If we're talking about #1, then there are only a few to choose from:
>>
>> Approval, Score, and Bucklin.
>>
>>
>> I suggest that all 3 of those should be offered to initiative-proposal
committees, and that the public should be polled, or consulted in
"focus-groups", regarding which of those 3 methods they'd  accept
>>
>>
>> For #2, it really takes something with a lot of valuable &
otherwise-unobtainable properties, to justify replacing Approval, Score or
Bucklin with it.
>>
>> I suggest that only Plain MMPO qualifies.
>>
>>
>>
>>>
>>>  Approval does well on 1,3,4, and 6, is OK on 2, and bad on 4 and 5.
>>
>>
>>
>> No. Contrary to what we so often hear, Approval doesn't have a high
strategic burden, as I discussed above.
>>
>> Other than MMPO's CD, improvements over Approval by more complicated
methods are illusory.
>>
>> And your standard #5 was summability and count-complexity. Approval is
precinct-summable, and its count is the easiest and least
computation-intensive, among voting-systems.
>>
>> Michael Ossipoff
>>
>>
>>
>>
>>
>>
>
>
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>
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