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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
[edit]Key
[edit]- Name (abbr.) and other names of the system (other names that may sometimes refer to other systems)
- Type of representation: the most common division of electoral systems
- Winner-take-all system (also called majoritarian representation): includes all single-winner systems; no guaranteed minority representation
- Proportional representation
- Semi-proportional representation
- Other: sortition, etc.
- Mixed system (yes/no): A systems composed of multiple other electoral systems, usually containing at least one proportional and one winner-take all system.
- Single-winner/multiple winner system
- List / candidate (personal election, also called nominal election) based system
- Type of ballot
- Decision rule
- No quotas
- Plurality (candidate or candidates with most votes wins, even if not majority of votes)
- Quota (candidates must at least reach the quota to be certain of election)
- Notable quotas
- Absolute majority (candidates must receive support at least half of voters
- Hare quota
- Droop quota
- Largest remainder method (supplemental method to using quotas)
- Multi-round voting (common supplemental method to using absolute majority
- Notable quotas
- Pairwise comparisons
- Simple majority rule
- Other
- No quotas
- Number of votes/voter
- Number of tiers: number of levels e.g. local, regional, state, national
Systems
[edit]| 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 round | Winner-take-all | No | single-winner | candidate | plurality | single choice | 1 | — |
| General ticket Party-block voting (PBV) | Winner-take-all | No | multi-winner (one slate) | list | plurality | single choice | 1 | — | |
| Plurality block voting (BV) plurality-at-large voting (multiple non-transferable vote, MTNV) | limited party block voting | Winner-take-all | No | multi-winner | candidate | plurality | multiple choice | =number of winners | — |
| Limited voting (LV) limited block voting partial block voting (multiple non-transferable vote, MNTV) | limited party block voting | semi-proportional | No | multi-winner | candidate | plurality | multiple choice | <number of winners | — |
| Single non-transferable vote (SNTV) | semi-proportional | No | multi-winner | candidate | plurality | single choice | 1 | — | |
| Single transferable vote (STV) Hare–Clark electoral system[2] (proportional ranked-choice voting)[3] | semi-proportional / proportional | No | multi-winner | candidate | quota | 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, | Winner-take-all | No | single-winner | candidate | majority | ranked choice (ordinal voting) | 1 (effectively) | — |
| Two-round system (TRS)[8] Runoff voting | Non-partisan primary, | Winner-take-all | No | single-winner | candidate | majority majoritarian | single choice | 1 (each round) | — |
| Two-round block voting (majority block voting)(multiple non-transferable vote, MNTV) | Winner-take-all | No | multi-winner | candidate | majority | multiple choice | =number of winners (each round) | — | |
| Multiple transferable vote (MTV) (Preferential block voting) | majoritarian | No | multi-winner | candidate | majority | ranked choice (ordinal voting) | =number of winners, effectively | — | |
| Exhaustive ballot | majoritarian | No | single-winner /multi-winner | candidate | majority | single choice | 1 | — | |
| Cumulative voting | panachage (certain types) | majoritarian / semi-proportional | No | single-winner /multi-winner | candidate | plurality | cumulative ballot | >1 | — |
| Approval voting (AV)[9] | block approval voting | majoritarian | No | single-winner /multi-winner | candidate | plurality | multiple choice | any number (max. one for one candidate) | — |
| Score voting Range voting | Approval voting (score voting 0-1) | majoritarian / semi-proportional | No | single-winner /multi-winner | candidate | plurality | score ballot(cardinal voting) | — | |
| Borda count | majoritarian / semi-proportional | No | single-winner /multi-winner | candidate | plurality | ranked choice (ordinal voting) | — | ||
| Condorcet method | Copeland's method, Dodgson's method, Kemeny–Young method, Minimax, Nanson's method, ranked pairs, Schulze method, Tideman's alternative methods | majoritarian | No | single-winner | candidate | majority against every candidate | ranked choice (ordinal voting) | — | |
| Party-list proportional representation list-PR | Largest remainderHighest averagesBinomial voting | semi-proportional / proportional | No | multi-winner | list (+ candidate, if open list) | quota or divisor method | single choice | 1 (effectively) | — |
| Superposition - non-compensatory combination of FPTP + List-PR (Supplementary member system) | Two-round system + List-PR | semi-proportional | Yes | multi-winner(+ single-winner in districts) | candidate + list | mixed non-compensatory | single choice | 2 (each tier) | 2 |
| Seat-linkage compensatory combination of FPTP + List-PR | mixed single vote versionbest-loser mixed-member proportional | semi-proportional / proportional | Yes | multi-winner(+ single-winner in districts) | candidate + list | mixed compensatory | single choice | 2 (each tier) | 2 |
| Vote-linkage compensatory combination of FPTP + List-PR Positive vote transfer system (PVT)[12] (mixed single vote - MSV[13]) (Additional member system - AMS) | negative vote transfer | semi-proportional / proportional | Yes | multi-winner(+ single-winner in districts) | candidate + list | mixed compensatory | single choice | 1 | 2 |
| Dual member proportional (DMP)[14] | semi-proportional / proportional | Yes | multi-winner (one elected by First-past-the-post voting; the other due to party list PR system | list or candidate | plurality (votes cast outside district have an effect) | single choice | 1 | 1 |
List of electoral systems used for national elections
[edit]| Electoral system | Subtype / combination | Type of representation | Countries and territories that use it to elect primary (lower) chamber of legislature |
|---|---|---|---|
| First-past-the-post (FPTP/FPP)[1] Single-member plurality (SMP/SMDP) | no | Winner-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 ticket Party-list plurality block voting (PBV) | no | Winner-take-all | Singapore |
| Plurality block voting (BV) plurality-at-large voting | no | Winner-take-all | Laos, Lebanon, Mauritius, Oman, Syria, Tonga, Tuvalu, Vietnam |
| Limited voting (LV) limited block voting | no | Semi-proportional | |
| Single non-transferable vote (SNTV) | no | Semi-proportional | |
| Single transferable vote (STV) | no | Semi-proportional / Proportional | Ireland, Malta |
| Instant-runoff voting (IRV)[4] | no | Semi-proportional | Australia, Papua New Guinea |
| Two-round system (TRS)[8] Runoff voting | no | Winner-take-all (single-winner) | France |
| Two-round block voting majority block voting | no | Winner-take-all | |
| Borda count | no | Semi-proportional | Nauru |
| Modified cumulative voting | no | Semi-proportional | Norfolk Island |
| Party-list proportional representation (list-PR) | Closed list | Proportional | |
| Closed list, locally personalized | Proportional | Germany | |
| Open list for some parties | Proportional | Colombia | |
| Open list | Proportional | Albania, 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 | |
| Panachage | Proportional | Ecuador, El Salvador, Honduras, Liechtenstein, Luxembourg, Switzerland | |
| Superposition - non-compensatory combination of FPTP + List-PR Parallel voting, Supplementary member system | FPTP + List-PR (two votes) | Semi-proportional | Cameroon, D.R.Congo, Japan, Kazakhstan, Kyrgyzstan, Nepal, Philippines, Russia, Taiwan, Venezuela, Thailand |
| FPTP + List-PR (tied votes) | Semi-proportional | Italy | |
| FPTP + List-PR (proportional to FPTP) | Winner-take-all / Semi-proportional | Pakistan, Tanzania, Zimbabwe | |
| TRS + List-PR | Semi-proportional | Egypt, Lithuania, Tajikistan | |
| BV/PBV + List-PR | Semi-proportional | Andorra, Mauritania, Senegal, Monaco | |
| Seat-linkage compensatory combination of FPTP + List-PR | FPTP + List-PR | Semi-proportional / Proportional | Bolivia, Lesotho, New Zealand |
| FPTP + List-PR (hybrid) | Semi-proportional | South Korea | |
| FPTP + List-PR (limited disproportionality) | Semi-proportional | Mexico | |
| Vote-linkage (compensatory) combination of FPTP + List-PR | FPTP + List-PR | Semi-proportional | Hungary |
| Majority bonus system | List-PR with plurality bonus | Semi-proportional | Greece |
| Majority jackpot system | Majority jackpot | Winner-take-all / Semi-proportional | Djibouti |
| Majority/minority jackpot | Semi-proportional | Armenia | |
| Two-round majority jackpot | Semi-proportional / Proportional | San Marino |
| Electoral system for national legislatures (lower house or unicameral) |
|---|
 |
Majoritarian representation (winner-take-all) Semi-proportional representation (non-mixed) No election (e.g. Monarchy) |
See also
[edit]References
[edit]- ^ a b "First past the post". nzhistory.govt.nz. Ministry for Culture and Heritage. 13 January 2016. Archived from the original on 24 May 2022. Retrieved 25 May 2022.
- ^ George Howatt, Democratic Representation under the Hare-Clark System – The Need for Seven-Member Electorates
- ^ "How RCV Works". FairVote. Archived from the original on 2022-05-25. Retrieved 2022-06-11.
- ^ a b 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. Archived from the original on 3 October 2018. Retrieved 11 June 2022.
- ^ "Alternative Vote". www.electoral-reform.org.uk. Archived from the original on 2019-05-28. Retrieved 2019-05-30.
- ^ FairVote.org. "Ranked Choice Voting / Instant Runoff". FairVote. Archived from the original on 7 January 2021. Retrieved 12 April 2021.
- ^ Pacuit, Eric (3 August 2011). "Voting Methods". Archived from the original on 21 November 2021. Retrieved 11 June 2022 – via plato.stanford.edu.
{{cite journal}}: Cite journal requires|journal=(help) - ^ a b "Two-Round System". Electoral Reform Society. Archived from the original on 12 December 2021. Retrieved 7 Nov 2019.
- ^ Brams, Steven; Fishburn, Peter (1978). "Approval Voting". American Political Science Review. 72 (3): 831–847. doi:10.2307/1955105. JSTOR 1955105. S2CID 251092061.
- ^ "Parallel —". aceproject.org. Archived from the original on 2022-04-27. Retrieved 2022-04-21.
- ^ a b "Additional-member system: Politics". Encyclopædia Britannica. Archived from the original on 8 April 2020. Retrieved 24 March 2016.
- ^ 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. doi:10.1080/00344893.2014.902222. S2CID 153691414.
- ^ Golosov, G. V. (2013). "The Case for Mixed Single Vote Electoral Systems". The Journal of Social, Political, and Economic Studies.
- ^ Graham, Sean (April 4, 2016). "Dual-Member Mixed Proportional: A New Electoral System for Canada". doi:10.7939/r3-qppp-b676. Archived from the original on December 4, 2020. Retrieved June 11, 2022.
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