List of electoral systems explained

An electoral system (or voting system) is a set of rules that determine how elections and referendums are conducted and how their results are determined.

Some electoral systems elect a single winner (single candidate or option), while others elect multiple winners, such as members of parliament or boards of directors.

The study of formally defined electoral methods is called social choice theory or voting theory, and this study can take place within the field of political science, economics, or mathematics, and specifically within the subfields of game theory and mechanism design.

List of electoral systems by types

Key

Systems

!Name(s)!Variations!Type of representation!Mixed?!Single/multi-winner!List-based OR candidate-based system!Type of decision rule!Type of ballot!Number of votes / voter!Number of tiers(if mixed)
First-past-the-post (FPTP/FPP)[1]
Single-member plurality (SMP/SMDP)
two-round system with lower than 50% requirement in first round1
General ticketParty-block voting (PBV)1
Plurality block voting (BV)plurality-at-large voting

(multiple non-transferable vote, MTNV)

limited party block votingmultiple choice=number of winners
Limited voting (LV)limited block voting

partial block voting

(multiple non-transferable vote, MNTV)

limited party block votingmultiple choice
Single non-transferable vote (SNTV)1
Single transferable vote (STV)Hare–Clark electoral system[2]

(proportional ranked-choice voting)[3]

ranked choice (ordinal voting)1 (effectively)
Instant-runoff voting (IRV)[4] (Alternative vote - AV)[5]

(Ranked-choice voting - RCV)[6]

(Single-transferable vote - STV)

(Hare's method)[7]

contingent vote,supplementary vote,Coombs' methodmajorityranked choice (ordinal voting)1 (effectively)
Two-round system (TRS)[8] Runoff votingNon-partisan primary,multi-round votingmajority majoritarian1 (each round)
Two-round block voting(majority block voting)(multiple non-transferable vote, MNTV)majoritymultiple choice=number of winners (each round)
Multiple transferable vote (MTV)(Preferential block voting)majorityranked choice (ordinal voting)=number of winners, effectively
Exhaustive ballotmajority1
Cumulative votingpanachage (certain types)cumulative ballot>1
Approval voting (AV)[9] block approval votingmultiple choiceany number(max. one for one candidate)
Score voting
Range voting
Approval voting (score voting 0-1)score ballot(cardinal voting)
Borda countranked choice (ordinal voting)
Condorcet methodCopeland's method, Dodgson's method,Kemeny–Young method,Minimax,Nanson's method,ranked pairs,Schulze method,Tideman's alternative methodsmajority against every candidateranked choice (ordinal voting)
Party-list proportional representationlist-PRLargest remainderHighest averagesBinomial voting1 (effectively)
Superposition - non-compensatory combination of FPTP + List-PR(Supplementary member system)

(Parallel voting)[10]

(Mixed-member majoritarian representation - MMM)

Two-round system + List-PRmixed single vote version(+ single-winner in districts) + listmixed non-compensatory2 (each tier)2
Seat-linkage compensatory combination of FPTP + List-PR(Additional member system - AMS)[11]

(Mixed-member proportional representation - MMP)

mixed single vote versionbest-loser mixed-member proportional(+ single-winner in districts) + listmixed compensatory2 (each tier)2
Vote-linkage compensatory combination of FPTP + List-PRPositive vote transfer system (PVT)[12]

(mixed single vote - MSV[13])

(Additional member system - AMS)

negative vote transfer(+ single-winner in districts) + listmixed compensatory12
Dual member proportional (DMP)[14] 11

List of electoral systems used for national elections

See main article: articles and List of electoral systems by country.

Electoral systemSubtype / combinationType of representationCountries and territories that use it to elect primary (lower) chamber of legislature
First-past-the-post (FPTP/FPP)
Single-member plurality (SMP/SMDP)
noWinner-take-all (single-winner)Antigua and Barbuda, Azerbaijan, Bahamas, Bangladesh, Barbados, Belarus, Belize, Bhutan, Botswana, Canada, Côte d'Ivoire, Dominica, Gambia, Ghana, Grenada, Jamaica, India, Kenya, Liberia, Madagascar, Malawi, Malaysia, Maldives, Micronesia, Myanmar, Nigeria, St. Kitts and Nevis, St. Lucia, Palau, Samoa, Solomon Islands, Trinidad and Tobago, Turkmenistan, Uganda, United Kingdom, St. Vincent and the Grenadines, Zambia
General ticketParty-list plurality block voting (PBV)noWinner-take-allSingapore
Plurality block voting (BV)plurality-at-large votingnoWinner-take-allLaos, Lebanon, Mauritius, Oman, Syria, Tonga, Tuvalu, Vietnam
Limited voting (LV)limited block votingnoSemi-proportional
Single non-transferable vote (SNTV)noSemi-proportional
Single transferable vote (STV)noSemi-proportional / ProportionalIreland, Malta
Instant-runoff voting (IRV)noSemi-proportionalAustralia, Papua New Guinea
Two-round system (TRS)Runoff votingnoWinner-take-all (single-winner)France
Two-round block votingmajority block votingnoWinner-take-all
Borda countnoSemi-proportionalNauru
Modified cumulative votingnoSemi-proportionalNorfolk Island
Party-list proportional representation (list-PR)Closed listProportional
Closed list, locally personalizedProportionalGermany
Open list for some partiesProportionalColombia
Open listProportionalAlbania, Algeria, Austria, Belgium, Brazil, Bulgaria, Chile, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Fiji, Finland, Iceland, Indonesia, Jordan, Kosovo, Latvia, Netherlands, Norway, Peru, Poland, Sierra Leone, Slovakia, Slovenia, Sri Lanka, Suriname, Sweden
PanachageProportionalEcuador, El Salvador, Honduras, Liechtenstein, Luxembourg, Switzerland
Superposition - non-compensatory combination of FPTP + List-PRParallel voting, Supplementary member systemFPTP + List-PR (two votes)Semi-proportionalCameroon, D.R.Congo, Japan, Kazakhstan, Kyrgyzstan, Nepal, Philippines, Russia, Taiwan, Venezuela, Thailand
FPTP + List-PR (tied votes)Semi-proportionalItaly
FPTP + List-PR (proportional to FPTP)Winner-take-all / Semi-proportionalPakistan, Tanzania, Zimbabwe
TRS + List-PRSemi-proportionalEgypt, Lithuania, Tajikistan
BV/PBV + List-PRSemi-proportionalAndorra, Mauritania, Senegal, Monaco
Seat-linkage compensatory combination of FPTP + List-PRAdditional member system - AMS

Mixed-member proportional representation - MMP

FPTP + List-PRSemi-proportional / ProportionalBolivia, Lesotho, New Zealand
FPTP + List-PR (hybrid)Semi-proportionalSouth Korea
FPTP + List-PR (limited disproportionality)Semi-proportionalMexico
Vote-linkage compensatory combination of FPTP + List-PRFPTP + List-PRSemi-proportionalHungary
Majority bonus systemList-PR with plurality bonusSemi-proportionalGreece
Majority jackpot systemMajority jackpotWinner-take-all / Semi-proportionalDjibouti
Majority/minority jackpotSemi-proportionalArmenia
Two-round majority jackpotSemi-proportional / ProportionalSan Marino

See also

References

  1. Web site: 13 January 2016 . First past the post . 25 May 2022 . nzhistory.govt.nz . . en . 24 May 2022 . https://web.archive.org/web/20220524111637/https://nzhistory.govt.nz/politics/fpp-to-mmp/first-past-the-post . live .
  2. George Howatt, Democratic Representation under the Hare-Clark System – The Need for Seven-Member Electorates
  3. Web site: How RCV Works . FairVote . 2022-06-11 . 2022-05-25 . https://web.archive.org/web/20220525013704/https://www.fairvote.org/how_rcv_works . live .
  4. Cary . David . 1 January 2011 . Estimating the Margin of Victory for Instant-runoff Voting . Proceedings of the 2011 Conference on Electronic Voting Technology/Workshop on Trustworthy Elections . EVT/WOTE'11 . 3 . 11 June 2022 . 3 October 2018 . https://web.archive.org/web/20181003061635/https://dl.acm.org/citation.cfm?id=2028012.2028015 . live .
  5. Web site: Alternative Vote . 2019-05-30 . www.electoral-reform.org.uk . en-US . 2019-05-28 . https://web.archive.org/web/20190528095548/http://www.electoral-reform.org.uk/voting-systems/types-of-voting-system/alternative-vote/ . live .
  6. Web site: FairVote.org . Ranked Choice Voting / Instant Runoff . 12 April 2021 . FairVote . 7 January 2021 . https://web.archive.org/web/20210107140218/https://www.fairvote.org/rcv . live .
  7. Pacuit . Eric . 3 August 2011 . Voting Methods . plato.stanford.edu . 11 June 2022 . 21 November 2021 . https://web.archive.org/web/20211121171052/https://plato.stanford.edu/archives/fall2019/entries/voting-methods/ . live .
  8. Web site: Two-Round System . 7 Nov 2019 . Electoral Reform Society . 12 December 2021 . https://web.archive.org/web/20211212121424/https://www.electoral-reform.org.uk/voting-systems/types-of-voting-system/two-round-system/ . live .
  9. Brams . Steven . Fishburn . Peter . 1978 . Approval Voting . American Political Science Review . 72 . 3 . 831–847 . 10.2307/1955105 . 1955105. 251092061 .
  10. Web site: Parallel — . 2022-04-21 . aceproject.org . 2022-04-27 . https://web.archive.org/web/20220427030522/https://aceproject.org/main/english/es/ese01.htm . live .
  11. Encyclopedia: Additional-member system: Politics . . 24 March 2016 . 8 April 2020 . https://web.archive.org/web/20200408184541/http://www.britannica.com/topic/additional-member-system . live .
  12. Bochsler . D . 2014 . Which mixed-member proportional electoral formula fits you best? Assessing the proportionality principle of positive vote transfer systems . Representation. 50 . 113–127 . 10.1080/00344893.2014.902222 . 153691414 .
  13. Golosov . G. V. . 2013 . The Case for Mixed Single Vote Electoral Systems . The Journal of Social, Political, and Economic Studies.
  14. Graham . Sean . April 4, 2016 . Dual-Member Mixed Proportional: A New Electoral System for Canada . 10.7939/r3-qppp-b676 . June 11, 2022 . December 4, 2020 . https://web.archive.org/web/20201204001722/https://era.library.ualberta.ca/items/e3ab993a-d264-4d30-b819-290ab5fd6b62 . live .