[EM] 2. Re: Methods (Markus Schulze)
S Sosnick
shsosnick at ucdavis.edu
Wed Jun 25 20:10:14 PDT 2014
Ballot used with Schulze's single-winner system.
Because the Schulze system determines who wins a one-winner election without
counting how many 1st choices each candidate received, its ranking ballot can differ
from the ranking ballot used with various other single-winner systems. Two
differences are especially noteworthy.
First, a voter can be allowed to assign the same rank to more than one candidate. That
voter's ballot will be ignored when comparing the equally-ranked alternatives but
counted when comparing one of the equally-ranked alternatives with some other
alternative. In contrast, with Instant-Runoff, Coombs, Borda, Bucklin, etc., a ballot
naming more than one 1st choice is invalid.
Second, one of the alternatives offered to voters can be "None of the above" or--as in
every statewide election in Nevada since 1975--"None of these candidates." If that is
done and a named candidate wins, then you can infer that the winner is, not only
preferred to the other named candidates, but also favored enough to be (say) hired.
Conversely, if "None" wins the election, then you might conclude that none of the
named candidates should be hired.
--Stephen H. Sosnick (25-Jun-14)
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> Today's Topics:
>
> 1. Re: PR for ethnically polarized electorates (Toby Pereira)
> 2. Re: Methods (Markus Schulze)
> 3. Re: Methods (robert bristow-johnson)
> 4. Re: PR for ethnically polarized electorates (Forest Simmons)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 25 Jun 2014 20:23:49 +0100
> From: Toby Pereira <tdp201b at yahoo.co.uk>
> To: Forest Simmons <fsimmons at pcc.edu>, EM
> <election-methods at lists.electorama.com>
> Subject: Re: [EM] PR for ethnically polarized electorates
> Message-ID:
> <1403724229.46921.YahooMailNeo at web133002.mail.ir2.yahoo.com>
> Content-Type: text/plain; charset="iso-8859-1"
>
> At first glance it seems that 10, 15 and 75 for A, B, M respectively seems
> a little optimistic from a voting system. It's not just that party list PR
> would shut out M - I can't see any system calling itself PR could award the
> seats in those proportions. Something like reweighted range voting or the
> score PR system I detailed a couple of weeks ago would stop M being shut
> out with honest voting, but they would go nowhere near as far as you are
> suggesting.
>
> Regarding voter honesty, it may be difficult to ensure it anyway with a
> normal score-based PR method, but I can't see how you could get it to work
> given that you would want the middle two factions' support for A and B to
> be effectively ignored. To be clear, 10, 15, 75 are the proportions
> you'd?expect if the 75 people who gave a positive score to M completely
> lost all their support for A/B and raised M to from 80 to 100.
>
> From: Forest Simmons <fsimmons at pcc.edu>
> >To: EM <election-methods at lists.electorama.com>
> >Sent: Wednesday, 25 June 2014, 1:21
> >Subject: [EM] PR for ethnically polarized electorates
> >
> >
> >
> >In Rwanda it was the Hutu and the Tutsi tribal division.? In Iraq the
> Sunni, Shia, and Kurds.? In the former Yugoslavia it was the Serbs Croats
> and Bosnians.? There are similar divisions today in the Ukraine, Israel,
> Syria, Bolivia, etc.
> >
> >What do they have in common?? A need for electing a representative body
> that has as many moderates and as much consensus as possible so that
> minorities are not so desperate for separation, i.e. to prevent the scourge
> of Balkanization that seems to be spreading like a plague.
> >
> >Suppose that there are two extreme groups A and B supported by two
> individual ethnicities, as well as a more moderate group M with preferences
> like
> >
> >
> >10 A(100)
> >30 A(100)>M(80)
> >
> 45 B(100)>M(80)
> >
> >15 B(100)
> >
> >
> >
> >(The numbers in parentheses represent voter expectations of relative
> benefits.)
> >
> >
> >In ordinary party list PR methods the parliament would be formed by 40
> representatives from A and 60 representatives from B.? The moderate party
> would be shut out entirely.
> >
> >
> >Here are my questions:
> >
> >
> >
> >1. What method(s) would take this information and elect a parliament with
> respective party strengths of? 10, 15, and 75? for A, B, and M?
> >
> >
> >2.? What election method could possibly get the two middle factions to
> honestly convey this information via their ballots?? In other words, how to
> keep the two middle factions from defecting from their common interest?
> >
> >
> >Forest
> >
> >
> >
> >----
> >Election-Methods mailing list - see http://electorama.com/emfor list info
> >
> >
> >
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>
> Message: 2
> Date: Wed, 25 Jun 2014 21:30:44 +0200
> From: Markus Schulze <markus.schulze at alumni.tu-berlin.de>
> To: election-methods at electorama.com
> Subject: Re: [EM] Methods
> Message-ID: <E1Wzsu9-0001BW-Cq at mailbox.alumni.tu-berlin.de>
> Content-Type: text/plain; charset="us-ascii"; format=flowed
>
> Hallo,
>
> > 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.
> >
> > 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.
>
> But if one of these candidates has to be chosen, the fact, that you like
> none of them, is quite irrelevant, because the legitimacy of the winner
> does not depend on how overwhelmingly he was chosen.
>
> Markus Schulze
>
>
>
> ------------------------------
>
> Message: 3
> Date: Wed, 25 Jun 2014 17:04:01 -0400
> From: robert bristow-johnson <rbj at audioimagination.com>
> To: election-methods at lists.electorama.com
> Subject: Re: [EM] Methods
> Message-ID: <53AB3941.4030702 at audioimagination.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> On 6/25/14 3:30 PM, Markus Schulze wrote:
> >
> > > A voting system should never give the impression that candidates that
> > > are universally loathed are ok. If our candidates were Adolf 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.
> > >
> > > 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.
> >
> > But if one of these candidates has to be chosen, the fact that you like
> > none of them is quite irrelevant, because the legitimacy of the winner
> > does not depend on how overwhelmingly he was chosen.
> >
>
> i can't tell whom you were responding to, Markus.
>
> i would ask the OP to suggest how the "sane voting system [that] *must*
> meet this requirement" does in the event that "None-of-the-above" wins.
> continue with the existing leadership in government and extend their
> term? for how long?
>
> also, how would Approval avoid this? would there be a minimum margin
> that, say, Mao would need to actually win, because certainly *some*
> voters will approve Mao in an Approval system. what thresholds of
> approval margin is needed to declare that Mao isn't so evil after all?
>
> as always, what do we do about multiple "approvals". perhaps, in
> comparison, i am least afraid of Mao and Idi compared to the others.
> but i fear Idi more than Mao. so i'm voting for Mao as the least of
> evils, should i approve Idi or not? what if Adolf gets elected because
> not enough of us voted for Idi who came in 2nd?
>
> i totally reject the notion that Approval voting or Score voting
> requires no (or the least) tactic from the voter.
>
> not to say there is no possibility of strategic voting with the ranked
> ballot decided with a Condorcet-compliant method, but any such strategy
> is quite sophisticated and likely to backfire (like trying to elect the
> "Radical Center" over the otherwise "Moderate" that might result in
> electing one extremist or another). it's *very* unlikely that an
> organized campaign to vote insincerely (say, by burying your sincere
> second choice in a go-for-broke strategy) on the ranked ballot will
> gather any significant support.
>
> setting aside a weird and sophisticated (and organized) strategy (which
> no one will want to risk), the voter has the easiest decision on how to
> vote with a ranked ballot. who's your favorite candidate? mark him or
> her #1. imagine if your favorite was not in the race at all, then who
> would be your favorite? mark him or her #2. really tough voting tactic.
>
> but with either Score or Approval, in a multi-candidate race, it's
> *always* difficult for the voter to decide how to vote for their second
> choice. do you approve your second choice or not? or how highly do you
> score your second choice? what if you help your second choice beat your
> first choice?
>
> i wish the Approval and Score advocates would move on from ridiculous
> scenarios and focus on the real problems we have in real elections.
>
> --
>
> r b-j rbj at audioimagination.com
>
> "Imagination is more important than knowledge."
>
>
>
>
>
> ------------------------------
>
> Message: 4
> Date: Wed, 25 Jun 2014 15:15:44 -0700
> From: Forest Simmons <fsimmons at pcc.edu>
> To: Toby Pereira <tdp201b at yahoo.co.uk>
> Cc: EM <election-methods at lists.electorama.com>
> Subject: Re: [EM] PR for ethnically polarized electorates
> Message-ID:
>
<CAP29oneWAh9dhh3YoOtcJ=1Qbv2cCM6RLLbeyn8VTYeNGuzW_A at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
>
> Thanks to Juho and Toby for their insights.
>
> It is true, as they suggest, that question 2 is the harder one.
>
> The simplest answer to question one that I know of is based on an idea
> that
> Martin Harper came up with 12 years ago as a way of showing that ordinary
> Approval satisfies "one voter one vote" in the same strict sense that IRV
> does (through vote transfer):
>
> First list the candidates in order of most approval to least approval.
> Then on each ballot transfer the entire support of the voter to the
> highest
> candidate on the list that is approved on the ballot. In other words, the
> voter's one and only vote is for the candidate she approves that is most
> approved by other voters. As Martin pointed out, this assignment of votes
> still elects the ordinary Approval winner in the single winner case.
> (Half
> a dozen years later Jobst pointed out that this same idea can be used to
> assign probabilities in a single winner lottery method.)
>
> I am now pointing out that Martin Harper's vote transfer scheme is a
> simple
> way of designing a PR method (based on approval ballots) that solves
> problem one. In the given example let us assume that the truncations are
> reliable indicators of disapproval. Then the approval ballots are
>
> 10 A
> 30 A, M
> 45 B, M
> 15 B
>
> The approval order is M>B>A
>
> The first faction ballots all count for A. The last faction ballots all
> count for B, and the other 75 ballots all count for M, yielding the
> desired
> quotas of 10, 15, and 75 respectively.
>
> Toby asks the question of why this M heavy proportion is so desirable.
>
> One answer is that in these polarized countries (the ones that inspired
> this thread in the first place) the fewer extremists in power the better.
> But in my next post, the one addressing question two, I will give a more
> dispassionate answer to that question.
>
> Forest
>
>
>
> On Wed, Jun 25, 2014 at 12:23 PM, Toby Pereira <tdp201b at yahoo.co.uk>
> wrote:
>
> > At first glance it seems that 10, 15 and 75 for A, B, M respectively
> seems
> > a little optimistic from a voting system. It's not just that party list
> PR
> > would shut out M - I can't see any system calling itself PR could award
> the
> > seats in those proportions. Something like reweighted range voting or
> the
> > score PR system I detailed a couple of weeks ago would stop M being shut
> > out with honest voting, but they would go nowhere near as far as you are
> > suggesting.
> >
> > Regarding voter honesty, it may be difficult to ensure it anyway with a
> > normal score-based PR method, but I can't see how you could get it to
> work
> > given that you would want the middle two factions' support for A and B
> to
> > be effectively ignored. To be clear, 10, 15, 75 are the proportions
> > you'd expect if the 75 people who gave a positive score to M completely
> > lost all their support for A/B and raised M to from 80 to 100.
> >
> > *From:* Forest Simmons <fsimmons at pcc.edu>
> > *To:* EM <election-methods at lists.electorama.com>
> > *Sent:* Wednesday, 25 June 2014, 1:21
> > *Subject:* [EM] PR for ethnically polarized electorates
> >
> > In Rwanda it was the Hutu and the Tutsi tribal division. In Iraq the
> > Sunni, Shia, and Kurds. In the former Yugoslavia it was the Serbs
> Croats
> > and Bosnians. There are similar divisions today in the Ukraine, Israel,
> > Syria, Bolivia, etc.
> >
> > What do they have in common? A need for electing a representative body
> > that has as many moderates and as much consensus as possible so that
> > minorities are not so desperate for separation, i.e. to prevent the
> scourge
> > of Balkanization that seems to be spreading like a plague.
> >
> > Suppose that there are two extreme groups A and B supported by two
> > individual ethnicities, as well as a more moderate group M with
> preferences
> > like
> >
> > 10 A(100)
> > 30 A(100)>M(80)
> > 45 B(100)>M(80)
> > 15 B(100)
> >
> > (The numbers in parentheses represent voter expectations of relative
> > benefits.)
> >
> > In ordinary party list PR methods the parliament would be formed by 40
> > representatives from A and 60 representatives from B. The moderate
> party
> > would be shut out entirely.
> >
> > Here are my questions:
> >
> > 1. What method(s) would take this information and elect a parliament
> with
> > respective party strengths of 10, 15, and 75 for A, B, and M?
> >
> > 2. What election method could possibly get the two middle factions to
> > honestly convey this information via their ballots? In other words, how
> to
> > keep the two middle factions from defecting from their common interest?
> >
> > Forest
> >
> >
> > ----
> > Election-Methods mailing list - see http://electorama.com/emfor list
> info
> >
> >
> >
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