[EM] Proportional multi-winner ranked voting methods - EPR

[Juho Laatu]

> entirely removes gerrymandering

Also this one is a useful property of a proportional method.

> by using a special ‘primary’


But adding a primary of course makes a method somewhat more complicated.

> In a relatively small city like Santa Cruz in which all 7 of the Councilmembers could be elected at large, such a ‘primary’ would probably be unnecessary.


If your districts have seven seats, there might be no need to add means to defend against gerrymandering. Gerrymandering is typically a problem of single seat districts.

> I mention RCV (i.e. IRV) because FairVote is currently campaigning for Santa Cruz to adopt RCV for electing its Council.


IRV is a single winner method for single seat districts. If you do it that way, you will not have good proportionality. STV would be a much better approach (also ranked and in many ways similar to IRV).

> 100 CITIZENS:
> 
> 40 prefer A over B over C
> 
> 40 prefer C over B
> 
> 20 prefer B over C


Condorcet criterion could be a natural requirement for single seat districts. It says that B should be elected since it would pairwise beat all other candidates.

But if we have multi-seat districts, Condorcet criterion could be forgotten. If we have two seats in this district, it would seem natural to elect A and C.

> at least 1/7 of all citizens who have voted


You could use also a somewhat lower threshold (e.g. Droop quota).

> 1)     if a voter has given more than one candidate the same relevant evaluation, her evaluation will be added only to the candidate whose total of evaluations would consequently be greater at that stage of the count than any of the other candidates she has given the same ‘grade’,


Does "at that stage of the count" mean that the order of the counted votes may have an impact on the outcome of the election? (depending on if X or Y happens to have more votes "at that stage of the count") Such randomness may be acceptable (if it keeps the method simple) but not a very good feature.

> To avoid the possibility of any one Councilmember being in a position to dictate to the Council, any Member who might have received more than 20% of all the ‘weighted votes’ in the Council, must publicly and non-returnably transfer her ‘extra’ votes to the ‘weighted votes’’ of one or more of her trusted fellow Members.


Would this candidate tell who will get his extra votes before or after the election? If before, then we might have some problems with cyclic transfers. If after, then we might have a problem with this candidate selling those votes to one of the other candidates. (There could be some smaller vote selling problems also in the case that candidates declare their preferences already before the election, but that is not as serious since voters can see (assuming that this information is public) where the votes will go.)

> Again, each Councilmember would have a ‘weighted vote’ in the Council exactly equal to the number of evaluations from citizens added to her total.


If we first elect one candidate with 1/7 of the votes rating him Excellent, his weight will be 1/7 of the total weight. All other candidates got zero Excellents. Next we count the Very Good ratings. One candidate gets them 2/7 of the total votes. Does this mean that the weight (voting power) of the second elected candidate will be higher than the weight of the first elected candidate? Note that it is possible that the first elected candidate had also lots of Very Good ratings. The question is if the weight of the first already elected candidate should be topped (maybe up to 20%) if he has lots of Very Good ratings.

> However, if a citizen’s vote still could not be added in this way to the ‘weighted vote’ of one of the candidates who has already been elected, EPR’s ballot allows a citizen to require the non-elected candidate to whom she had given her highest evaluation, to transfer her one vote to the ‘weighted vote’ of the Councilmember he believes is the one most qualified for the office.


Maybe that requirement would be automatic. Maybe the method would be too complex to the voters otherwise. It is also typical that election methods try to hide how each voter voted, and not allow anyone to find that out (for privacy, vote buying and coercion related reasons).

The direction of transfer could also here be declared before or after the election. Similar problems might occur as discussed already above. If we don't want to lose a single vote, and the candidates give the inheritance order before the election, they might have to rank all the candidates (quite tedious for the candidates, and also for the voters to read).

I guess the 20% rule applies somehow also here.

>  1. It prompts citizens firstly to consider what qualities that are ideally required of the office being sought.


Most election methods do this somehow.

> 2. By allowing citizens to express the full range of their evaluations of as many of the candidates as they might wish ...


Many election methods allow ballots that are equally rich in expressing the opinions. Some methods may lose this richness because of tactical voting (e.g. in Range many voters might use only min and max values).

> 3. Also, unlike other multi-winner methods, EPR allows each citizen to guarantee that his or her vote will continue fully to count quantitatively and qualitatively in the deliberations of their city council


It is a nice feature that no votes are lost, and they will all be used in the city council. I think there are however no guarantees that their votes will count also "qualitatively" (in the sense that the voting behaviour of the representatives would reflect the opinions of the voters more accurately (in some other sense than "every single vote having a representative") than in some other kind of elections).

> 4. In addition to the above advantages, since ‘grading’ candidates is easier than ‘ranking’ them, this makes it more like that each voter will see EPR as more user-friendly than the ‘ranking’ methods.


Not necessarily since it is quite easy to use "graded" ballots and derive rankings from them, if the method is ok with having equal rankings. That would make voting equally easy in both approaches.

My overall impression is that this method is on a reasonably good track if we start from the assumption that the society accepts the basic idea of having representatives with different weights.

If the candidate opinion based vote transfers get too complex, you might consider also the more traditional approach of letting fellow party members to inherit all the extra votes. This might fall slightly short of your target of directing each vote to some clearly named single representative, but you might gain simplicity and understandability and you might get rid of the vote selling related questions.

Juho



> On 25 Nov 2017, at 02:49, steve bosworth <stevebosworth at hotmail.com> wrote:
> 
> 
> 
> 
> Re: Proportional multi-winner ranked voting methods vs. Evaluative PR (EPR)
> 
> Date: Fri, 24 Feb 2017 01:09:59 +0200
> From: Juho Laatu <juho.laatu at gmail.com>
> To: EM <election-methods at lists.electorama.com>
> Subject: Re: [EM] Proportional multi-winner ranked voting methods -
>         guidelines?
> Message-ID: <4A6DBFF9-B2E2-4284-86CA-0F3E8ACAB241 at gmail.com>
> Content-Type: text/plain; charset=utf-8
> 
> Today's Topics:   2. Re: Proportional multi-winner ranked voting methods -
>       guidelines? (Juho Laatu)
> 
> 
> Juho Laatu juho.laatu at gmail.com <> wrote:
> 
> I just note that it would be useful to have some numeric requirements available when the usefulness of different proportional voting methods is evaluated. Some useful numbers (and other requirements) could be the number of candidates per district (e.g. 200, maybe 30 for each party), number of seats per district (e.g. 30), number of districts (e.g. 15), variation in the size of the districts (e.g. from 3 to 30 seats), handling of "overflow" and "lost" votes (e.g. votes to small parties in a district that has only 3 seats), required accuracy of proportionality (e.g. droop or hare proportionality at national level, or separately at each district), requirement of equal treatment of parties that get their support from one district only vs. evenly from all districts, planned style and accepted complexity of the ballots or voting machines, ability to vote for individual candidates, ability to vote multiple individual candidates across party borderlines, accuracy of party internal proportionality, ability to vote for one's favourite party (e.g. vote to one candidate inherited by other candidates of the party).
> 
> Hi Juho,
>  
> With respect to each of your elements that I’ve underlined above, I see Evaluative Associational PR (EAPR) as offering the most democratically attractive method for electing a nation’s legislative assembly.  However, I would greatly appreciate your feedback, both with regard to this claim and on the following explanations.  What do you think?
>  If you want a copy of my fully explained of EAPR  I will email it to you (stevebosworth at hotmail.com).  However, this post more briefly explains a simplified version of EAPR for electing the Council for a small city. I call this version Evaluative PR (EPR) because it does not include the feature in EAPR that entirely removes gerrymandering by using a special ‘primary’ to elect all the electoral ‘associations’ (geographically defined or not) which would nominate all the candidates to run in the national election.  In a relatively small city like Santa Cruz in which all 7 of the Councilmembers could be elected at large, such a ‘primary’ would probably be unnecessary.  This is because these useful ‘associations’ could easily form themselves spontaneously in the context of using EPR in a small city. 
> 
> I’ll explain EPR in contrast to Single Transferrable Voting (STV, i.e. RCV for electing multi-winners).  I mention RCV (i.e. IRV) because FairVote is currently campaigning for Santa Cruz to adopt RCV for electing its Council.  Instead, EPR (& EAPR) uses a modification of Majority Judgment (MJ -- Belinski & Laraki, 2010).  I see MJ and EPR as better than RCV because ‘evaluating’ candidates’ ‘fitness’ for the office is more meaningful, discerning, and informative than merely ‘ranking’ them.  It also offers a lower incentive and less scope for voting dishonestly (manipulation, etc.).   At the same time, ‘grading’ candidates is easier to do than ‘ranking’ them.  In addition, EPR avoids the problem with RCV methods that they can require the elimination of some candidates who are preferred by more citizens before the count is finished.  With ERP, all the evaluations of all the candidates by all the voters continue to count until all the most valued candidates are discovered to be the winners.
>  
> EPR vs. RCV
> Of course, RCV would be a great improvement on existing arrangements for electing a city council or any legislature. However, I hope to show that Evaluative Proportional Representation (EPR) would more efficiently and completely support all the values and objectives put forward in favor of RCV.
> 
> Again, one key disadvantage of RCV is that it can require some candidates who are preferred by more voters to be eliminated before the winners are discovered.  For example, if 100 citizens vote in the following way, RCV would make candidate C win.  B would be eliminated by RCV even though she is preferred by more citizens:  20 citizens’ 1st preference votes and by 80 citizens’ 2nd preference votes.  Candidate C is supported only by 40 1st preference votes and by 20 2nd preference votes.  Candidate A is supported only by a different group of 40 1st preference votes.  Still RCV elects C:
> 
> 100 CITIZENS:
> 
> 40 prefer A over B over C
> 
> 40 prefer C over B
> 
> 20 prefer B over C
> 
> Fortunately, there are other methods that do not suffer from this flaw, e.g.  Evaluative Proportional Representation (EPR) is based on Majority Judgment (MJ) thinking (Belinski & Laraki, 2010, MIT press).  MJ is for electing a single winner (e.g. a governor or a president).
> 
> Instead, of asking each voter to ‘rank’ as many of the candidates they might wish, MJ and EPR ask voters to ‘grade’ as many of the candidates they might wish, i.e. to grade each candidate’s suitability for the office as being either EXCELLENT, VERY GOOD, GOOD, ACCEPTABLE, POOR or as REJECTED.  Any candidate not explicitly graded is counted as having been REJECTED by that voter.   With MJ, the winning candidate is the one who has the ‘highest median-grade’, i.e. the candidate to whom at least a majority have awarded at least this highest grade.  If more than one candidate has the same highest median-grade, the winner is discovered by removing any grades equal in value to this grade (one-by-one) from each tied candidate’s total until only one of the previously tied candidates is found to retain the highest median-grade.  Like RCV, this guarantees that the winner will have been supported quantitatively at least by a majority of those voting.  However, the MJ winner is more likely to be of a higher quality because he or she has been expressly evaluated more highly than any of the other candidates.  
>  
> Also, ‘grading’ is easier than ‘ranking’ and grading also has the advantage of prompting citizens to think about what qualities make a candidate ‘fit’ for the office.  Grades are more informative, ‘discerning’ and ‘meaningful’ than numbers.  In addition, unlike other methods, EPR enables each citizen to guarantee that her one vote will continue fully to count in the deliberations of the Council.
> 
> EPR EXPLAINED
> Ideally, all 7 members of Santa Cruzes City Council should be elected at the same time, all running at-large.  During this election, each citizen would be asked to evaluate as many of the candidates as they might wish, i.e. giving each, one of the above ‘grades’.  Any candidate not marked by a voter would be counted as Rejected by that voter.  The first candidate to be elected would be the one, if any, who had received the highest number of Excellents above or at the threshold, i.e. at least 1/7 of all citizens who have voted. 
> To honor the principle of one-person-one-vote,
> 1)     if a voter has given more than one candidate the same relevant evaluation, her evaluation will be added only to the candidate whose total of evaluations would consequently be greater at that stage of the count than any of the other candidates she has given the same ‘grade’,
> 2)     all the evaluations given to other candidates by voters who have already helped to elect an earlier candidate would play no part in electing any later candidate, and
> 3)     each elected candidate would have a ‘weighted vote’ in the Council exactly equal to the number of citizens who had helped to elect them.  
> In this way, it will be seen that each EPR citizen can guarantee that her one vote will continue fully to count in the deliberations of the Council.  To avoid the possibility of any one Councilmember being in a position to dictate to the Council, any Member who might have received more than 20% of all the ‘weighted votes’ in the Council, must publicly and non-returnably transfer her ‘extra’ votes to the ‘weighted votes’’ of one or more of her trusted fellow Members.  This means that any majority decision within the Council would require the agreement of at least 3 of the 7 Councilmembers.
> The second candidate to be elected would be the one, if any, who had received the next highest number of remaining Excellents above or equal to the threshold (1/7).  The next candidates to be chosen, one by one, would be the ones, if any, who had received the next highest number of remaining Excellents above or equal to the threshold.  These would compose the first group of candidates to be elected.   
> Similarly, the second group of candidates to be chosen, one by one, would be the ones, if any, who had received the highest number of evaluations as a result of also adding all the remaining Very Goods, then Goods (the third group), and then Acceptables (the fourth group). 
>  
> If the total number of winners within these four groups proved to be less than the required 7, the fifth and final group would be composed of the remaining number of Councilmembers required to complete the 7, i.e. still those most highly evaluated candidates and receiving a number of evaluations closest to the above threshold.  Again, each Councilmember would have a ‘weighted vote’ in the Council exactly equal to the number of evaluations from citizens added to her total.
> 
> Finally, the vote of any citizen whose vote had not yet been counted toward the ‘weighted vote’ of an elected candidate as a result of any of the above counts would now be added if possible to the ‘weighted vote’ of the Councilmember to whom she had given at least an evaluation of Acceptable.  However, if a citizen’s vote still could not be added in this way to the ‘weighted vote’ of one of the candidates who has already been elected, EPR’s ballot allows a citizen to require the non-elected candidate to whom she had given her highest evaluation, to transfer her one vote to the ‘weighted vote’ of the Councilmember he believes is the one most qualified for the office.  In this way, unlike RCV, each citizen can guarantee that their one vote will continue fully to count in the deliberations of the Council through the Councilmember she probably values most highly – no citizen’s vote need be wasted. 
> 
> Consequently, I now see ERP as democratically superior to all other known methods for electing a legislative body because:
> 
>  1. It prompts citizens firstly to consider what qualities that are ideally required of the office being sought.
>  2. By allowing citizens to express the full range of their evaluations of as many of the candidates as they might wish, this makes the results of an EPR election likely to be more discerning and informative than those provided by any other method, including RCV (e.g. plurality or First-Past-The- Post (FPTP), APPROVAL, SCORE (RANGE), Condorcet (e.g. Maximize Affirmed Majorities (MAM), open or closed Part-List, or Mixed Member PR).
>  3. Also, unlike other multi-winner methods, EPR allows each citizen to guarantee that his or her vote will continue fully to count quantitatively and qualitatively in the deliberations of their city council (or their elected state or national legislature when using EAPR).
>  4. In addition to the above advantages, since ‘grading’ candidates is easier than ‘ranking’ them, this makes it more like that each voter will see EPR as more user-friendly than the ‘ranking’ methods.
>  5. Unlike Ranked Choice Voting (RCV), EPR does not waste any citizens’ votes, nor eliminate any candidate before all the most valued winners have been discovered.
>  6. As contrasted to all other methods except FPTP and Part-List, EPR provides a lower incentive or less scope for citizens to vote dishonestly (manipulatively, strategically, tactically, etc.).
> 
> What do you think?    I look forward to your questions and feedback.
> Steve (stevebosworth at hotmail.com)
> 
>  
> 
> 
> ----
> Election-Methods mailing list - see http://electorama.com/em for list info

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