[EM] Can anyone help with straight-ahead Condorcet language?

[Daniel Carrera]

On Tue, Sep 21, 2021 at 10:38 AM robert bristow-johnson <
rbj at audioimagination.com> wrote:


> Here is Bottom-Two Runoff:
>
> ___________________________________________________________________________
>
> All elections of [office] shall be by ballot, using a system of
> ranked-choice voting without a separate runoff election. The presiding
> election 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. Lower ordinal preference shall be considered higher
> rank and the candidate marked as first preference is considered ranked
> highest. Equal ranking of candidates shall not be allowed. Any candidate
> not marked with a preference shall be considered as ranked lower than every
> candidate marked with a 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 retabulation shall be performed by the presiding election officer.
> The instant runoff retabulation shall be conducted in sequential rounds. A
> "continuing candidate" is defined as a candidate that has not been defeated
> in any previous round. Initially, no candidate is defeated and all
> candidates begin as continuing candidates.
>   (4) In each round, every ballot shall count as a single vote for
> whichever continuing candidate the voter has ranked highest. The two
> candidates with the fewest votes in a round, herein denoted as "A" and "B",
> shall contend in a runoff in which the candidate, A or B, with lesser voter
> support shall be defeated in the current round. If the number of ballots
> ranking A higher than B exceeds the number of ballots ranking B higher than
> A, then B has lesser voter support, B is defeated, and A continues to the
> following round. Likewise, if the number of ballots ranking B higher than A
> exceeds the number of ballots ranking A higher than B, then A has lesser
> voter support, A is defeated, and B continues to the following round. In
> the case that the aforementioned measures of voter support of A and B are
> tied, then the candidate with fewest votes is defeated in the current round.
>   (5) The aforementioned instant runoff retabulation, eliminating one
> candidate each round, shall be repeated until only two candidates remain.
> The remaining candidate then receiving the greatest number of votes is
> elected.
>   (6) The [governing jurisdiction] may adopt additional regulations
> consistent with this subsection to implement these standards.
> ___________________________________________________________________________
>
> If step (4) above can be made better, I would be interested in seeing it.
>


You can reuse the ordinal system to simplify (4):

(4) In each round, every ballot shall count as a single vote for whichever
continuing candidate the voter has ranked highest. The two candidates with
the fewest votes in a round, herein denoted as "runoff candidates", shall
contend in a runoff. In each runoff, every ballot shall count as a single
vote for whichever runoff candidate the voter has ranked highest. The
candidate with the fewest votes is defeated in the current round.






>
> Here is straight-ahead Condorcet (version 1, most like Daniel's):
>
> ___________________________________________________________________________
>
> All elections of [office] shall be by ballot, using a system of
> ranked-choice voting without a separate runoff election. The presiding
> election 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. Lower ordinal preference shall be considered higher
> rank and the candidate marked as first preference is considered ranked
> highest. Equal ranking of candidates shall be allowed. Any candidate not
> marked with a preference shall be considered as ranked lower than every
> candidate marked with a 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, a
> Condorcet-consistent retabulation shall be performed by the presiding
> election officer. The candidate, who is the Condorcet winner, is elected if
> the rankings on all of the ballots indicate that this one candidate
> defeats, with a simple majority of voter preferences, every other candidate
> when compared in turn with each other individual candidate. A selected
> candidate defeats another candidate by a simple majority when the number of
> ballots marked ranking the selected candidate higher than the other
> candidate exceeds the number of ballots marked to the contrary.
>   (4) If no Condorcet winner exists in step (3), then the candidate with
> the plurality of first preferences is elected.
>   (5) The [governing jurisdiction] may adopt additional regulations
> consistent with this subsection to implement these standards.
> ___________________________________________________________________________
>
>
> Here is another straight-ahead Condorcet (version 2):
>
> ___________________________________________________________________________
>
> All elections of [office] shall be by ballot, using a system of
> ranked-choice voting without a separate runoff election. The presiding
> election 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. Lower ordinal preference shall be considered higher
> rank and the candidate marked as first preference is considered ranked
> highest. Equal ranking of candidates shall be allowed. Any candidate not
> marked with a preference shall be considered as ranked lower than every
> candidate marked with a 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, a
> Condorcet-consistent retabulation shall be performed by the presiding
> election officer. The retabulation shall examine each possible pairing of
> candidates. If N is the number of candidates, including combined Write-In,
> then the number of possible pairings of candidates is N(N-1)/2. For each
> possible pairing of candidates, if fewer ballots are marked preferring a
> selected candidate over the other candidate than the number of ballots
> marked to the contrary, then the selected candidate is marked as defeated.
> After all candidate pairs are examined, the candidate who remains unmarked
> as defeated is the Condorcet winner and is elected.
>   (4) If no Condorcet winner exists in step (3), then the candidate with
> the plurality of first preferences is elected.
>   (5) The [governing jurisdiction] may adopt additional regulations
> consistent with this subsection to implement these standards.
> ___________________________________________________________________________
>
>
> In the last two, I want to keep all of the steps the way they are, but if
> step (3) can be made better, that is what I am groping for.
>
> Concise is good, but it **must** be complete and clear in normal usage of
> the American English language.
>



Here is a more concise rewrite of your first version:

(3) If no candidate receives a majority of first preferences, the presiding
officer shall perform a series of two-candidate runoffs where every
candidate has a runoff with every other candidate. Each runoff between two
candidates is won by the candidate that is ranked higher by a majority of
ballots. A candidate that wins all of their runoffs is the Condorcet winner
and is elected.

Cheers,
-- 
Dr. Daniel Carrera
Postdoctoral Research Associate
Iowa State University
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