[EM] Methods

Dave Ketchum davek at clarityconnect.com
Sat Oct 22 13:40:52 PDT 2011


On Oct 18, 2011, at 10:13 PM, Dave Ketchum wrote:

> Quoting Mike Ossipoff:  'to me, our current public political  
> elections don't require any strategy decisions, other than "vote for  
> acceptable candidates and don't vote for the entirely unacceptable  
> ones."'
>
> In the discussions of Approval and ranking, below, Mke's thought  
> applies to both.  In the extreme, when this leaves no one to vote  
> for, simply vote for none (or, if forced, do whatever forced to do  
> for one candidate).
>
> In Approval we have a count of how many considered each candidate  
> acceptable; with ranking we have counts in an x*x matrix as to how  
> many preferred each candidate over each other candidate.

Some write later as if not understanding what I have written, so I  
will try emphasizing:

Being acceptable for electing by me means approvable via Approving or  
ranking, and not acceptable means I should not approve via either  
method, for I will not want to be part of getting lemons elected  
either way.

Thus the minimum of what can be done with ranking is the same as the  
ability of Approval, and no less, while ranking has additional  
abilities normally used.

More can be and normally is done with the abilities ranking offers,  
but this is not the lack some seem to see - the x*x matrix, used as  
part of counting in most ranking methods, is an informative summary as  
to ranking details.

Dave Ketchum
>
> On Oct 18, 2011, at 4:28 PM, Kristofer Munsterhjelm wrote0
>
>> matt welland wrote:
>>> On Mon, 2011-10-17 at 20:42 +0200, Kristofer Munsterhjelm wrote:
>>>> matt welland wrote:
>>>>> Again, I think it is very, very important to note that the ranked
>>>>> systems actually lose or hide information relative to approval  
>>>>> in both
>>>>> these cases.
>>>> In what manner does a ranked method hide information? Neither  
>>>> ranked ballot methods nor strategic Approval can distinguish  
>>>> between "everybody's equally good" and "everybody's equally bad".
>>>>
>>>>> Note that in the first case the results and impact of a ranked  
>>>>> system
>>>>> are actually worse than the results of approval. The political  
>>>>> pressure
>>>>> to converge and appeal to a broad spectrum is greater under  
>>>>> approval
>>>>> than the ranked systems. The evaluation of a voting system only  
>>>>> makes
>>>>> sense in the context of all the other things going on in a  
>>>>> society. The
>>>>> pressure on politicians to actually meet the needs of the people  
>>>>> is a
>>>>> massively important factor and ranked systems appear to wash out  
>>>>> some of
>>>>> that force which is a very bad thing IMHO.
>>>> Again, why is that the case? In Approval, you're either in or  
>>>> you're out; but in ranked methods, the method can refine upon  
>>>> those two groups and find the better of the good (be that by  
>>>> broad or deep support relative to the others). If anything, this  
>>>> finer gradient should increase the impact, not decrease it,  
>>>> because the search will more often be pointed in the right  
>>>> direction.
>>> A ranked system cannot give the feedback that all the candidates are
>>> disliked (e.g. all candidates get less than 50% approval). It also
>>> cannot feedback that all the candidates are essentially equivalent  
>>> (all
>>> have very high approval).
>
> While it is agreed that counts in Approval show the above, it needs  
> seeing that the x*x matrix can be read in the same way for ranking.
>
>> Neither does strategic Approval. In Approval, the best simple  
>> strategy (if I remember correctly) is to approve the perceived  
>> frontrunner you prefer, as well as every candidate who you like  
>> better. In a Stalin election, if people were perfectly rational,  
>> the left-wingers would approve Stalin if the other frontrunner was  
>> Hitler.
>>
>> Well, perhaps people aren't perfectly rational. However, to the  
>> degree they are honest, Approval can get into a contending third- 
>> party problem. If you have a parallel universe where Nader is  
>> nearly as popular as Gore, liberals would have to seriously (and  
>> strategically) think about whether they should approve of Gore or  
>> not - if too many approve of Gore *and* Nader, Nader has no chance  
>> of winning; but if too many approve of only Nader, Bush might win.
>>
>>> Ranked systems essentially normalize the vote. I think this is a  
>>> serious
>>> issue. A ranked system can give a false impression that there is a
>>> "favorite" but the truth might be that none of the candidates are
>>> acceptable.
>
> See above.
>>
>>
>> Some ranked methods can give scores, not just rankings. As a simple  
>> example, the Borda count gives scores - the number of points each  
>> candidate gets - as a result of the way it works. The Borda count  
>> isn't very good, but it is possible to make other, better methods  
>> give scores as well; and if you do so, an "equally good/equally  
>> bad" situation will show as one where every candidate gets nearly  
>> the same score.
>>
>> As for distinguishing "equally bad" from "equally good", there are  
>> two ways you could do so within ranked votes. You could do it  
>> implicitly, by assuming that the voters approve of the candidates  
>> they rank and disapprove of those they don't; or you can do it  
>> explicitly by adding a "against all" (re-open nominations, none of  
>> the below, etc) virtual candidate.
>
> Adding a virtual candidate is making trouble for voters UNLESS its  
> good justifies its pain.
>>
>>
>>> Ironically by trying to capture nuances the ranked systems have  
>>> lost an
>>> interesting and valuable part of the voter feedback.
>>> A voting system should never give the impression that candidates  
>>> that
>>> are universally loathed are ok. If our candidates were Adol Hitler,
>>> Joseph Stalin, Pol Pot, Idi Amin, Benito Mussolini, Mao Zedong and
>>> Leopold II of Belgium then approval would rightly illustrate that  
>>> none
>>> are good candidates. However a ranked system would merely indicate  
>>> that
>>> one of them is the "condorcet" winner giving no indication that  
>>> none are
>>> acceptable.
>
> Again, x*x is useful and available and ranking has no more need for  
> sick ranking than does Approval.
>>
>>
>> Here, an implicit solution would record heaps of blank votes, and  
>> an explicit one would show the virtual candidate to be the CW.
>>
>>> I think any sane voting system *must* meet this requirement. The  
>>> ability
>>> for the electorate to unambiguously communicate that none of the
>>> candidates are worthy of the post under contest. I don't know how  
>>> to prove it but my hunch is that approval would be more
>>> resistant to manipulation by the so-called "one percenter" elites  
>>> than
>>> ranked systems.
>
> Apparently this theory was designed without adequate understanding  
> of ranking.
>>
>>
>> James Green-Armytage's paper seems to show Approval as one of the  
>> rules more vulnerable to strategic voting (see http://www.econ.ucsb.edu/~armytage/svn2010.pdf 
>>  ). Whether or not that would translate into one-percenter  
>> manipulation, however, I don't know. I suspect that most of the  
>> rules (e.g. various Condorcet methods, Approval, Majority  
>> Judgement) would be sufficiently resistant. Even top-two seems to  
>> do well enough to break Duverger's law.

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