[EM] Burlington VT reconsidering IRV 10 years after IRV failed to elect the Condorcet Winner

[robert bristow-johnson]

How does this look to you guys?  This is the original language on the existing resolution to implement RCV that is not Condorcet compliant:

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All elections of mayor, city councilors and school commissioners shall be by ballot, using a system of ranked choice voting without a separate runoff election. The chief administrative officer shall implement a ranked choice voting protocol according to these guidelines:
  (1) The ballot shall give voters the option of ranking candidates in order of preference.
  (2) If a candidate receives a majority (over 50 percent) of first preferences, that candidate is elected.
  (3) If no candidate receives a majority of first preferences, an instant runoff re-tabulation shall be performed by the presiding election officer. The instant runoff re-tabulation shall be conducted in rounds. In each round, each voter’s ballot shall count as a single vote for whichever continuing candidate the voter has ranked highest. The candidate with the fewest votes after each round shall be eliminated until only two candidates remain, with the candidate then receiving the greatest number of votes being elected.
  (4) The city council may adopt additional regulations consistent with this subsection to implement these standards.

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and here is the original languate modified to implement BTR-STV that is Condorcet compliant:


________________________________________________________


All elections of mayor, city councilors and school commissioners shall be by ballot, using a system of ranked choice voting without a separate runoff election. The chief administrative officer shall implement a ranked choice voting protocol according to these guidelines:
  (1) The ballot shall give voters the option of ranking candidates in order of preference.
  (2) If a candidate receives a majority (over 50 percent) of first preferences, that candidate is elected.
  (3) If no candidate receives a majority of first preferences, an instant runoff re-tabulation shall be performed by the presiding election officer. The instant runoff re-tabulation shall be conducted in sequential rounds. A "remaining candidate" is defined as a candidate that has not been eliminated in any previous round. Initially, no candidate is eliminated and all candidates begin as remaining candidates.
  (4) In each round, each voter’s ballot shall count as a single vote for whichever remaining candidate the voter has ranked highest. The two candidates with the fewest votes in a round, herein designated as "A" and "B", shall be compared in a runoff in which the candidate, A or B, with lesser voter support is eliminated in the same round. If the number of ballots having A ranked higher than B exceeds the number of ballots having B ranked higher than A, then B has lesser voter support, B is eliminated, and A remains for the following round. Likewise, if the number of ballots having B ranked higher than A exceeds the number of ballots having A ranked higher than B, then A has lesser voter support, A is eliminated, and B remains for the following round. In the case that the aforementioned measure of voter support between A and B is tied, then the candidate with fewest votes is eliminated in the same round.
  (5) This runoff re-tabulation, eliminating one candidate each round, is repeated until only two candidates remain, with the candidate then receiving the greatest number of votes being elected.
  (6) The city council may adopt additional regulations consistent with this subsection to implement these standards.

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Is this good language for BTR-STV?  Can any of you think of a hole in this description?  Can any of you make it better or more concise?

Thank you.

r b-j


> On December 3, 2019 3:44 PM Kristofer Munsterhjelm <km_elmet at t-online.de> wrote:
> 
>  
> On 03/12/2019 16.54, robert bristow-johnson wrote:
> > 
...
> > 
> > I want to figure out some good language to change this from regular-old IRV to Bottom-Two Runoff, Single Transferable Vote, BTR-STV .  If someone is good at writing legal language or if this BTR-STV has had legislative language written for it somewhere else, I would like to see it.
> > 
> > The language that needs to be changed, to make this RCV Condorcet-compliant is: 
> > 
> > "... The candidate with the fewest votes after each round shall be eliminated ..."
> > 
> > How can we clearly and concisely change that to Bottom-Two Runoff?
> 
> My first stab would be: "After each round, of the two candidates with
> the fewest votes, the candidate ranked below the other by the most
> voters shall be eliminated".
> 
> Alternatively "on the most ballots". Or "among the two candidates". Or
> "of the two candidates with the fewest votes in that round".
> 
> Presumably there has to be some tie-breaking language for the case where
> more than one candidate is last or next-to-last. But I suppose there is
> some similar language for IRV as is.
> 
> If there is no equal-rank or truncation, you can also say "the candidate
> ranked below the other by a majority of the voters".
> 
> The strategy to turn IRV into BTR-IRV is probably the best one. Woodall
> is better than BTR-IRV, and you could turn the method into Woodall by
> checking for a CW before a round starts, but then you'd have to define
> what a CW means in a way that doesn't confuse people who are unfamiliar
> with Condorcet.
> 
> Looking again at the language, point (3) is already rather convoluted.
> Perhaps it would be better to split up the definition. Something like:
> 
> (3) If no candidate receives a majority of first preferences, an instant
> runoff re-tabulation shall be performed by the presiding election
> officer. The instant runoff re-tabulation shall be conducted in rounds.
> In each round, each voter’s ballot shall count as a single vote for
> whichever continuing candidate the voter has ranked highest, and
> subsidiarily to determine what candidate to eliminate. After each round,
> the two candidates with the fewest votes shall be considered for
> elimination. Of these two candidates, the candidate ranked below the
> other by the most voters shall be eliminated in that round. The counting
> in rounds shall continue until only two candidates remain, with the
> candidate then receiving the greatest number of votes being elected.
> 
> (Maybe also call it something else than "instant runoff re-tabulation"
> because it's no longer IRV, but I can't think of a better name at the
> moment.)
> 
> I'm much less certain about Woodall. See below for something I cooked up.
> 
> (1) The ballot shall give voters the option of ranking candidates in
> order of preference.
> (2) If a candidate receives a majority (over 50 percent) of first
> preferences, that candidate is elected.
> (3) If no candidate receives a majority of first preferences, an instant
> runoff re-tabulation shall be performed by the presiding election
> officer. The instant runoff re-tabulation shall be conducted in rounds,
> for which the counting shall be conducted according to the following
> three points.
> (4) If there exists a continuing candidate so that for every other
> continuing candidate, the former candidate is ranked ahead of the latter
> by a majority of the voters, the former candidate is elected.
> (5) If there is no such candidate, each voter’s ballot shall count as a
> single vote for whichever continuing candidate the voter has ranked
> highest. The candidate with the fewest votes shall be eliminated, which
> marks the end of the current round and the beginning of the next.
> (6) The counting in rounds shall continue until a candidate is elected
> or only one candidate remains, with the remaining candidate then being
> elected.
> (7) The city council may adopt additional regulations consistent with
> this subsection to implement these standards.
> 
> (Strictly speaking, the latter half of point 6 is redundant because when
> only two candidates remain, the winner beats the loser pairwise and
> would be elected by point 4. But a potentially infinite loop looks more
> dangerous than a finite one.)
> 
> I haven't written legislative language before, but maybe it can serve as
> a starting point for others who have.
> 
> -km

--

r b-j                  rbj at audioimagination.com
 
"Imagination is more important than knowledge."