Proportional representation: Difference between revisions

'''Proportional representation''' ('''PR''') characterizes [[electoral system]]s in which divisions in an electorate are reflected proportionately in the elected body.<ref name=JSM7>{{cite book|last1=Mill|first1=John Stuart|author-link=John Stuart Mill|title=Considerations on Representative Government|chapter=Chapter VII, Of True and False Democracy; Representation of All, and Representation of the Majority only |chapter-url=http://www.gutenberg.org/files/5669/5669-h/5669-h.htm#link2HCH0007 |year=1861 |publisher=Parker, Son, & Bourn |location=London|title-link=Considerations on Representative Government}}</ref> The most widely used families of "proportional representation" electoral systems are [[party-list proportional representation|party-list PR]], the [[singlemixed-member transferableproportional voterepresentation]] (STVMMP), and the [[mixed-membersingle proportionaltransferable representationvote]] (MMPSTV).<ref name="DouglasHowPrElecWork">{{cite web|last=Amy|first=Douglas J|title=How Proportional Representation Elections Work |url=http://www.fairvote.org/how_proportional_representation_elections_work |publisher=[[FairVote]]| access-date=26 October 2017}}</ref>

OneThe [[Partisan system|partisan]] definition for "proportional representation" is that the candidates are partitioned into disjoint parties, and each voter approves all candidates in a single party. For example,<ref>{{Cite book|last=Piotr Faliszewski, Piotr Skowron, Arkadii Slinko, Nimrod Talmon|chapter-url=https://books.google.com/books?id=0qY8DwAAQBAJ&q=multiwinner++voting+a+new+challenge&pg=PA27|title=Trends in Computational Social Choice|date=2017-10-26|publisher=Lulu.com|isbn=978-1-326-91209-3|editor-last=Endriss|editor-first=Ulle|language=en|chapter=Multiwinner Voting: A New Challenge for Social Choice Theory}}</ref> suppose we need to elect a committee of size 10. Suppose that exactly 50% of the voters approve all candidates in party A, exactly 30% approve all candidates in party B, and exactly 20% approve all candidates in party C. Then, proportional representation requires that the committee contains exactly 5 candidates from party A, exactly 3 candidates from party B, and exactly 2 candidates from party C. If the fractions are not exact, then some rounding method should be used, and this can be done by various [[Apportionment (politics)|apportionment methods]]. However, in approval voting there is a different challenge: the voters' approval sets might not be disjoint. For example, a voter might approve one candidate from party A, two candidates from B, and five from C. This raises the question of how proportional representation should be defined. PeopleThe definingconcepts of "[[justified representation]]" areone tryingapproach to dosolving thatthis problem.

Countries which have semi-proportional representation systems include: [[Australia]], [[Germany]], [[Hungary]], [[India]], [[Republic of Ireland]], [[Italy]], [[Japan]], [[Mexico]], [[New Zealand]], [[Thailand]] and [[Wales]]. [[India]] is one ofperhaps the mostlargest successfuldemocracy exampleswhich ofuses a countryform withof proportional representation.

Whenever more than a [[Hare Quota]] of the voters gives max support to a single candidate and min support to every other candidate, that candidate is guaranteed to win regardless of how any of the other voters vote. This is explicitly formalized for approval ballots as [[Justified_representation#Proportional_justified_representation | Proportional justified representation ]].

In asset voting,<ref name=smithMultisurv/><ref name=smithAssetMultiwin>{{cite web|last=Smith|first=Warren|title="Asset voting" scheme for multiwinner elections|url=http://rangevoting.org/WarrenSmithPages/homepage/multiwin.pdf|date=8 March 2005}}</ref> the voters vote for candidates and then the candidates negotiate amongst each other and reallocate votes amongst themselves. Asset voting was proposed by [[Lewis Carroll]] in 1884<ref>{{cite web |url=https://archive.org/details/ThePrinciplesOfParliamentaryRepresentation |title=The Principles of Parliamentary Representation |last=Dodgson |first=Charles |date=1884 |publisher=London: Harrison and Sons |access-date=28 June 2019 |quote=The Elector must understand that, in giving his vote to ''A'', he gives it to him as his absolute property, to use for himself, or to transfer to other Candidates, or to leave unused.}}</ref> and has been more recently independently rediscovered and extended by [[Warren D. Smith]] and [[Forest Simmons]].<ref name=smithAssetWeb>{{cite web|last=Smith|first=Warren|title=Asset voting – an interesting and very simple multiwinner voting system|url=http://rangevoting.org/Asset.html|access-date=4 April 2016}}</ref> As such, this method substitutes candidates' collective preferences for those of the voters.

Similar to [[Majority Judgment]] voting that elects single winners, Evaluative Proportional Representation (EPR) elects all the members of a legislative body. Both systems remove the qualitative wasting of votes.<ref>{{cite book|author= M. Balinski & R. Laraki|year=2010|title=Majority Judgment. |publisher=MIT |isbn=978-0-262-01513-4}}</ref> Each citizen grades the fitness for office of as many of the candidates as they wish as either Excellent (ideal), Very Good, Good, Acceptable, Poor, or Reject (entirely unsuitable). Multiple candidates may be given the same grade by a voter. Using EPR, each citizen elects their representative at-large for a city council. For a large and diverse state legislature, each citizen chooses to vote through any of the districts or official electoral associations in the country. Each voter grades any number of candidates in the whole country. Each elected representative has a different voting power (a different number of weighted votes) in the legislative body. This number is equal to the total number of votes given exclusively to each member from all citizens. Each member's weighted vote results from receiving one of the following from each voter: their highest grade, highest remaining grade, or proxy vote. No citizen's vote is "[[wasted vote|wasted]]"<ref>{{cite journal |first1=Stephen |last1=Bosworth |first2=AnderAnders |last2=Corr |first3=Stevan |last3=Leonard |name-list-style=amp |title=Legislatures Elected by Evaluative Proportional Representation (EPR): an Algorithm |url=http://www.jpolrisk.com/legislatures-elected-by-evaluative-proportional-representation-epr-an-algorithm-v2/|journal=Journal of Political Risk |volume=7 |number=8 |date=July 8, 2019 |access-date=August 19, 2019}}</ref> Unlike all the other proportional representation systems, each EPR voter, and each self-identifying minority or majority is quantitatively represented with exact proportionality. Also, like Majority Judgment, EPR reduces by almost half both the incentives and possibilities for voters to use Tactical Voting. {{See also|Tactical voting#Majority judgment}}

SystemsA designedfew tocities havein highthe levelsUnited ofStates Proportionaluse representationSTV, doincluding havePortland, someOR, historyAlbany, inCA, thePalm UnitedDesert, StatesCA, Cambridge, MA, and [https://fairvote.org/our-reforms/proportional-ranked-choice-voting-information/ a couple of others]. Many cities in the past, including New York, oncealso had used such systems for their city councils as a way to break up the Democratic Party monopolies on elective office. In Cincinnati, Ohio, a system was adopted in 1925 to get rid of Republican party dominance but was successfully overturned in 1957.

** [https://www.fairvote.org/proportional_representation_libraryarchives/proportional-representation-library/ FairVote]

[[Category:Proportional voting methods|*]]