Single transferable vote: Difference between revisions
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(Add references section, Benham elimination mechanism, and reference to a variant of ER-STV(Whole)) |
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* Disallowing them, requiring full rankings
* Counting a ballot with N top-ranked candidates as 1/N of a vote for each candidate.
* Giving one vote to each equally-top-ranked candidate. Can optionally be combined with a suggestion that ballots that equally rank candidates shouldn't be able to prevent the elimination of those candidates.<ref name="reddit 2011">{{cite web | title=Proportionality failure in STV with equal-ranks with whole votes : EndFPTP | website=reddit | date=2019-12-05 | url=https://www.reddit.com/r/EndFPTP/comments/e6bt6s/proportionality_failure_in_stv_with_equalranks/f9thuy4/?context=8&depth=9 | access-date=2020-02-10}}</ref>
=== Methods of transferring excess votes ===
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* Standard STV: Eliminate the candidate with the fewest top-choice votes.
* [[BTR-STV]]: Eliminate the pairwise loser of the bottom two candidates (meets [[Condorcet criterion]] in single-winner elections).
* [[Benham's method|Benham]]: If the candidate with the fewest top-choice votes beats every other remaining candidate pairwise, eliminate the candidate with the next fewest top-choice votes. Meets the [[Condorcet criterion]] in single-winner elections.
* [[STV-CLE]]: Eliminate the loser of a [[Condorcet ranking]]
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4. Eliminate the candidate with the fewest 1st choices and redistribute their voters' votes to their next preferences. Go to step 2.
* Conceptually speaking, the candidates who are eliminated during the STV portion of the count could be said to be eliminated from contention for the first N - 1 seats, but still remain in contention for the final seat; though technically, it's possible for the final seat to be filled during the STV count itself (i.e. in a 2-seat election, 2 candidates might each have a quota of 1st choices and automatically win).<ref name="reddit pseudo">{{cite web | title=Pseudocode for STV with Condorcet for the final seat : EndFPTP | website=reddit | date=2020-02-08 | url=https://www.reddit.com/r/EndFPTP/comments/f0muwv/pseudocode_for_stv_with_condorcet_for_the_final/ | access-date=2020-02-10}}</ref></blockquote>If the single-winner method passes the [[Majority criterion|majority criterion]], then this modification makes STV with Droop quotas become the single-winner method in the single-winner case, since a candidate with a Droop quota of 1st choices is the majority's 1st choice in the single-winner case. If STV with Hare Quotas is used instead, then this modification can be used with any single-winner method that passes [[Pareto criterion|unanimity]] and reduce to that single-winner method in the single-winner case.
5-winner example:<blockquote>45 L1 > L2 > L3 > C > R2 > R1
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*[http://www.stvaction.org.uk STV Action - a group campaigning for STV]
== References ==
{{fromwikipedia}}
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