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{{merge|Preferential voting|date=August 2022|target=Ranked voting}}
{{Wikipedia|Ranked voting}}
[[Image:Preferential ballot.svg|thumb|Sample ballot of ranked voting using written numbers]]
'''Ranked voting''' is any election [[voting system]] in which voters use a '''ranked
The similar term "Ranked Choice Voting" (RCV) is used by the US organization [[FairVote]] to refer to the use of ranked ballots with specific counting methods: either [[instant-runoff voting]] for single-winner elections or [[single transferable vote]] for multi-winner elections. In some locations, the term "preferential voting" is used to refer to this combination of ballot type and counting method, while in other locations this term has various more-specialized meanings.<ref name=":02"/>
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There are many types of ranked voting, with several used in governmental elections. [[Instant-runoff voting]] is used in Australian state and federal elections, in Ireland for its presidential elections, and by [[Ranked-choice voting in the United States|some jurisdictions in the United States]], United Kingdom, and New Zealand. A type and classification of ranked voting is called the [[single transferable vote]], which is used for national elections in Ireland and Malta, the Australian Senate, for regional and local elections in Northern Ireland, for all local elections in Scotland, and for some local elections in New Zealand and the United States. [[Borda count]] is used in [[Slovenia]]<ref>{{Cite journal|last=Toplak|first=Jurij|title=The parliamentary election in Slovenia, October 2004|journal=Electoral Studies|volume=25|issue=4|pages=825–831|doi=10.1016/j.electstud.2005.12.006|year=2006}}</ref> and [[Nauru]]. [[Contingent vote]] and [[Supplementary vote]] are also used in a few locations. [[Condorcet method]]s are used by [[Schulze method#Users|private organizations and minor parties]], but currently are not used in governmental elections.
[[Arrow's impossibility theorem]] and [[Gibbard's theorem]] prove that all voting systems must make trade-offs between desirable properties, such as the preference between two candidates being unaffected by the popularity of a third candidate.<ref name=Mankiw>{{cite book | title=Principles of Microeconomics | publisher=South-Western Cengage Learning | first=Gregory |last=Mankiw | edition=6th| year=2012 | isbn=978-0538453042 |pages=475–479
Recently, an increasing number of authors, including [[David Farrell (political scientist)|David Farrell]], [[Ian McAllister (political scientist)|Ian McAllister]] and [[Jurij Toplak]], see preferentiality as one of the characteristics by which electoral systems can be evaluated.<ref name=":02">{{Cite journal|last=Toplak|first=Jurij|date=2017|title=Preferential Voting: Definition and Classification|journal=Lex Localis – Journal of Local Self-Government|volume=15|issue=4|pages=737–761|doi=10.4335/15.4.737-761(2017)}}</ref><ref>{{Cite journal|last1=Farrell|first1=David M.|first2=Ian|last2=McAllister|date=2004-02-20|title=Voter Satisfaction and Electoral Systems: Does Preferential Voting in Candidate-Centered Systems Make A Difference|url=http://repositories.cdlib.org/csd/04-04|language=en}}</ref> According to this view, all electoral methods are preferential, but to different degrees and may even be classified according to their preferentiality.<ref name=":02" /> By this logic, [[cardinal voting]] methods such as [[Score voting]] or [[STAR voting]] are also "preferential".
== Types of ranked voting ==
See [[:Category:Ranked voting methods|Category:Ranked voting methods]].
=== Single-winner methods ===
In general, most ranked methods attempt to extend [[majority rule]] to elections with more than two candidates. Some ranked methods do this using some kind of [[runoff]] i.e. [[IRV]] and [[Condorcet method]]<nowiki/>s, which explains why many of them pass the [[Condorcet loser criterion]].
[[IRV]] is yhe most popular ranked method. It is an attempt to give voters in [[FPTP]] a chance to add support to new alternatives when their candidate is polling the worst in the race. This opens it to criticisms of limiting the [[Number of supportable candidates in various voting methods]], as well as inducing odd [[Strategic voting]].
The [[Borda count]] is an example of a [[Weighted positional method]], not all of which aim for majority rule, in which points are given to candidates based on their rank. These are related to [[Cardinal method]]<nowiki/>s.
[[Bucklin]] finds a majority winner by essentially looking for the median voter's preferred candidate. See [[:Category:Graded Bucklin methods|Category:Graded Bucklin methods]].
[[Smith-efficient]] [[Condorcet methods]] can be thought of as maximally combining compliance with the [[majority criterion]] in the two-candidate case with [[Independence of irrelevant alternatives]].
=== Multi-winner methods ===
[[STV]] is the major ranked [[PR]] method, with there being several alternatives such as the [[Quota Borda system]] or the [[Expanding Approvals Rule]]. For ranked [[Block voting]] elections, any ranked single-winner method can be used by repeatedly electing the candidates at the top of its [[order of finish]].
== Criticisms ==
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[[Score voting]] takes this a step further by allowing voters to vary their degree of approval; in some sense, this can be seen in the ranked context by first using the [[KP transform]] and then converting the resulting Approval ballots into ranked ballots as mentioned above. This allows voters to essentially "vote against themselves" in certain matchups or otherwise split their ballot up in such a way that only a fraction of it shows a preference between certain candidates, while the rest of the ballot is treated as indifferent between those candidates i.e. a voter giving 100% support to A, 70% to B, and 10% for C is treated as 10% of an A=B=C voter, 60% of an A=B voter, and 30% of an A voter, thus allowing them to have, for example, only 60% of their ballot showing preference for B>C, rather than 100%. Again, the same "the strength of X>Z is equal to X>Y plus Y>Z" beat-or-tie path consistency is achieved here; if analyzing the A vs C matchup, the voter gives 90% of their ballot to A>C and 10% to A=C, so they are in effect giving 0.9 votes to A>C. This equals the strength of the A vs B matchup (0.3 votes for A>B, since the voter gives 30% of their ballot to A>B and 70% to A=B) plus the B vs C matchup (60% or 0.6 votes for B>C, as mentioned above).
=== Misordering ===
Most ranked voting methods can incentivize voters to [[Strategic voting|strategically]] vote by ranking candidate Y above X even though the voter preferred X to Y (though the frequency and degree of incentive depend on the method). For this reason, it is claimed that [[Score voting]] is better, because it doesn't incentivize this, and thus may be even better at collecting ranked-preference information than most ranked methods.<ref>{{Cite web|url=https://www.reddit.com/r/EndFPTP/comments/fcexg4/score_but_for_every_pairwise_matchup/fjl1hg3|title=r/EndFPTP - Comment by u/MuaddibMcFly on ”Score but for every pairwise matchup”|website=reddit|language=en-US|access-date=2020-05-14}}</ref>
== Majority rule as an approximation of utilitarianism ==
It is important to emphasize that majoritarianism and cardinal utilitarianism are not necessarily opposing principles. From a utilitarian perspective, majoritarianism can be considered an [[Majority_criterion#Majority_rule_as_an_approximation_of_utilitarianism|approximation of utilitarian principles]] under certain conservative assumptions. This is analogous to how most systems of ethics can be cast as varieties of utilitarianism with constraints on the utilities being used, even systems that are not utilitarian ''as such''.
== Discussion ==
It is worth considering what a ranked method's "approval case" looks like. This is when, if equal rankings are permitted, all voters rank every candidate either 1st or last. Many ranked methods become [[Approval voting]] in their approval case i.e. the candidate with the most 1st choices wins (sometimes this depends on how equal-rankings are implemented); for example, all [[Smith-efficient]] [[Condorcet methods]], [[Borda]], [[IRV]] with [[Equal-ranking methods in IRV|whole votes equal-ranking]], etc.
== References ==
<references/>
[[Category:Ballot types]]
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