[EM] Proportional multi-winner ranked voting methods - guidelines?

Thu Feb 23 09:54:23 PST 2017

On 2/22/2017 3:45 PM, Richard Lung wrote:
 >
 > Don't understand your remark about STV ...
 > ... for a single national constituency.
 > ...
 > The HG Wells formula is "Proportional representation by the single
 > transferable vote in large constituencies."

I assume you are referring to this statement:

 >> STV (the Single Transferable Vote) and similar methods(!) are designed
 >> for a small number of available seats, and it is a mistake to think
 >> that such a method can simply be used repeatedly to achieve fair
 >> results for a large number of available parliament seats.

Although the designers think that they designed STV to handle a full 
national legislature/parliament, the method has the same flaw as 
instant-runoff voting (IRV), namely the method looks at each voter's 
currently top choice (after any candidate eliminations), and that 
approach -- of assuming the candidate with the most such "votes" is the 
most popular (or the inverse, assuming that the candidate with the 
fewest such votes is least popular) -- is extremely flawed.

In other words, STV is like using single-mark ballots, except that when 
a voter's marked candidate is eliminated, then the voter automatically 
supplies an alternate single-mark ballot.

In spite of that major unfairness/flaw, STV would provide reasonably 
acceptable results if only two seats were being filled.  And if a nation 
has 3 equally dominant political parties, then filling 3 seats for each 
district would work.

However, as I stated before, STV would not provide fair results if it 
were used for a full national legislature.

Recently, in Canada, some people have been promoting the idea of using 
STV to elect about 5 MPs (members of parliament) from each district 
(which they call a "riding").  That would produce very unfair results! 
That's what I had in mind when I referred to using STV repeatedly.

Although Schulze-STV uses pairwise counting, it still has the same flaw 
that it would not provide overall proportional results if it were used 
repeatedly to fill more than 2 (or maybe 3) seats in each district.  And 
this method, and similar methods, would also provide flawed results if 
it were used to fill all the seats in a national legislature (and those 
reasons are explained in my book).

So, OK, I was not clear about the meaning of the word "designed."  I was 
referring to the effect of the design rather than the intention of the 
design.

Richard Fobes

On 2/22/2017 3:45 PM, Richard Lung wrote:
>
> Don't understand your remark about STV, the name given by Thomas Hare,
> who invented it for a single national constituency. (Tho Mill was
> prepared to be flexible about this, when he moved "Mr Hare's system" of
> Personal Representation in parliament.
> The HG Wells formula is "Proportional representation by the single
> transferable vote in large constituencies."
>
> Agree with you about preference voting essential for fairness. Do you
> have any good source for your assertion that the lack of it in European
> party-proportional methods makes them especially vulnerable to moneied
> influence?
> You could say the same, for instance about the nuclear lobby in Britain
> (tho not Scotland).
>
> from Richard Lung.
>
>
>
> On 22/02/2017 00:24, VoteFair wrote:
>> On 2/20/2017 11:57 PM, Armando wrote:
>> > ...
>> > I am looking for multi-winner election with fair proportional
>> > representation.
>> > ...
>> > I would very appreciate if you can help me giving “guidelines”,
>> > explaining pros and cons, advising further readings. ...
>>
>> I suggest that you look at VoteFair ranking, which is a method I
>> developed years ago, over a span of about a decade.
>>
>> It is described in detail in my book "Ending The Hidden Unfairness In
>> U.S. Elections," which is available through multiple e-book reading
>> platforms.  The book includes lots of illustrations to make the
>> concepts easier for "average" (non-math) readers to understand.  (With
>> so many illustrations the file size is large and the low price
>> basically just covers the download fee.)
>>
>> Near the end of the book I explain that the same system would work in
>> other nations simply by increasing the number of parliament members
>> who are elected using cross-district voting methods.
>>
>> Based on your questions, here is what I think is the most important
>> concept for you to understand:
>>
>> STV (the Single Transferable Vote) and similar methods(!) are designed
>> for a small number of available seats, and it is a mistake to think
>> that such a method can simply be used repeatedly to achieve fair
>> results for a large number of available parliament seats.
>>
>> You seem to correctly understand that ranking candidates -- rather
>> than using single-mark ballots -- is essential for fair results.  PR
>> (proportional representation) methods in Europe did not get this part
>> of PR correct.  That's why it is easy for campaign contributions
>> (money) to easily control European politics.
>>
>> With these concepts in mind, I suggest that you read the overview of
>> VoteFair ranking, which is here:
>>
>> http://www.votefair.org/calculation_details.html
>>
>> Or, for your convenience, here is a copy of those words, but without
>> the links:
>>
>> ........ begin quote ..........
>>
>> VoteFair ranking is a calculation method that includes the following
>> components:
>>
>> * VoteFair popularity ranking, which identifies the most popular
>> choice, the second-most popular choice, the third-most popular choice,
>> and so on down to the least popular choice.  Here is a link to details
>> about VoteFair popularity ranking.
>>
>> * VoteFair representation ranking, which identifies the
>> most-representative choice (which is the same as the most popular
>> choice according to VoteFair popularity ranking), the second-most
>> representative choice, and additional representation levels.  The
>> second-most representative choice is identified after appropriately
>> reducing the influence of the voters who are well represented by the
>> most-popular (and most-representative) choice.  Without this
>> adjustment the same voters who are well-represented by the most
>> popular choice could also determine the second-place winner.  Here is
>> a link to details about VoteFair representation ranking.
>>
>> * VoteFair party ranking, which identifies the most-popular political
>> party (which is the same as the most popular choice according to
>> VoteFair popularity ranking), the second-most popular political party
>> (which is the same as the second-most representative choice), and the
>> political party that deserves to be recognized as the third-most
>> popular political party.  The third-most popular party is identified
>> after appropriately reducing the influence of the voters who are well
>> represented by the first-ranked and second-ranked political parties.
>> Without this adjustment the same voters who are well-represented by
>> one of the most popular parties could create a "shadow" party that
>> occupies the third position, which would block smaller parties from
>> that third position.  Here is a link to details about VoteFair party
>> ranking.
>>
>> * VoteFair partial-proportional ranking, which identifies candidates
>> who failed to win a legislative seat in their district, yet deserve to
>> win special legislative seats for the purpose of compensating for
>> unfair district boundaries, making it possible to elect legislators
>> from "third" political parties (especially when the main political
>> parties fail to fully represent their political priorities.  Without
>> this adjustment the balance of power among political parties in the
>> legislature can easily fail to match the voters' preferences for
>> political parties.  Here is a link to details about VoteFair
>> partial-proportional ranking.
>>
>> ........ end quote ..........
>>
>> For details about any part of VoteFair ranking, please go to the
>> webpage and click the appropriate link.
>>
>> Thanks for your interest in learning how voting should be done!
>>
>> If you have questions, just ask.
>>
>> Richard Fobes
>> Author of "The Creative Problem Solver's Toolbox" which has been
>> published around the world in 10 languages
>>
>>
>>
>> On 2/20/2017 11:57 PM, Armando wrote:
>>> Hello,
>>> I am a new subscriber, and I am not an expert.
>>>
>>> I am looking for multi-winner election with fair proportional
>>> representation.
>>> I would like to find a method allowing voters to vote “transversally”
>>> through parties: it could decrease conflicts.
>>> I would very appreciate if you can help me giving “guidelines”,
>>> explaining pros and cons, advising further readings. I thank you very
>>> much in advance.
>>>
>>> I would like to open two issue:
>>>
>>> *1. Best multi-winner ranked method for a PROPORTIONAL ASSEMBLY*
>>>
>>> I read of CIVS
>>> <http://civs.cs.cornell.edu/proportional.html> and Schulze-STV
>>> <https://en.wikipedia.org/wiki/Schulze_STV>, and I thought they where
>>> the best for my case.
>>> They seems better then “traditional” STV since they satisfy more
>>> criteria, with less strategic vote risk.
>>> However I don’t understand differences among various condorcet’s
>>> multi-winner systems.
>>>
>>> I knew also De Borda-based multiwinner systems:
>>> _http://www.deborda.org/faq/_
>>> It seems De Borda got popular in the spanish party of Podemos recently:
>>> but they used a non-proportional De Borda to elect their national
>>> assembly (with DesBorda
>>> <https://vistalegre2.podemos.info/la-asamblea/#Sistema_de_votacion> by
>>> Echenique).
>>> Others in the same party proposed (failing) the Dowdall variant
>>> <https://forms.podemos.info/wp-content/uploads/gravity_forms/247-6edda8669dd26a992ea894158e3e3d91/2016/12/PropuestaPodemosEnMovimiento.pdf>
>>>
>>> of De Borda (it is used in Nauru’s elections too). It seems it would
>>> have been more proportional (here a simulation
>>> <http://www.eldiario.es/politica/datos-cocina-votaciones-Podemos_0_612089572.html?utm_content=buffer93f9f&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer>,
>>>
>>> 3rd figure, compare /Sistema utilizado (/DesBorda) with /Propuesta de
>>> Anticapitalista/ (Dowdall-Borda)).
>>>
>>> However De Borda Institute recommends Quota Borda
>>> System
>>> http://www.deborda.org/faq/voting-systems/what-is-the-quota-borda-system-qbs.html
>>>
>>>
>>> Actually I think there are few differences, for voters, between a
>>> condorcet and a borda ballot (always numbering candidates). Is it?
>>> But what are the difference in /results, /considering the proportional
>>> variants?
>>>
>>> Do you think PR-open list system helps more the more “conflictual”
>>> candidates (as could be the leader of each party, since they are
>>> overexposed to party electors “love” and to opposers “hate”)?
>>>
>>> *2*. *Best multi-winner ranked method for a PROPORTIONAL MIXED-PARTIES
>>> GOVERNMENT*
>>> I was fascinated by De Borda Institute’s idea: a system to elect
>>> directly a mixed government, where voters choose candidates AND best
>>> offices for them.
>>> They call it Matrix
>>> Vote
>>> http://www.deborda.org/faq/voting-systems/what-is-the-matrix-vote.html
>>>
>>> Could be possible to reach this purpose also with other systems, for
>>> example Schulze-stv?
>>>
>>>
>>> Best regards,
>>> Thank you in advance
>>>
>>> Armando Pitocco
>>>
>>>
>>>
>>>
>>>
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>
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