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Approval Voting

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Approval Voting is a system of voting designed to allow voters to vote for, or “approve” of, as many or as few candidates as they wish. In a single-member constituency, the candidate with the most votes wins, just as in first past the post (FPTP), with the difference being that the vote tally reflects the broadest overall approval rather than the plurality of voters who selected that candidate as their favourite. Approval Voting is technically the simplest example of a Score votingWikipedia system,[1][note 1] with the range of scores being limited to two choices: 0 (non-approval) or 1 (approval). Thus, it is also the simplest possible method of cardinal votingWikipedia.[2][note 2]

A 2011 survey of 22 prominent experts on voting procedures published by École Polytechnique[3] gleaned their views on 18 different voting systems, and found that Approval Voting was endorsed by the most experts[note 3] (68%), followed by Alternative Vote a.k.a. Instant Runoff Voting (45%), while FPTP – the voting system currently in use throughout the U.S. and the U.K. – came out rock-bottom with 0% of the experts endorsing it.

Like Instant Runoff Voting (IRV), Approval Voting is one of the foremost voting systems being suggested for implementation in the United States, with its main advocate being the Center for Election ScienceWikipedia (CES). Fargo in North Dakota became the first U.S. City to adopt the method for its mayoral elections in 2018,[4] with 64% of the public supporting the change.[5] In 2020, St. Louis in Missouri adopted a variant of Approval Voting for its municipal office votes.[6]

Electoral reform advocates in the United States, however, are divided on which voting system is best: the Center for Range Voting is on board with Approval Voting[7] but prefers full Range voting a.k.a. Score voting,[8][9] the Equal Vote Coalition pushes STAR votingWikipedia,[10][note 4] while FairVoteWikipedia disagrees and endorses Ranked Choice Voting (RCV) instead — specifically IRV.[11] Hopefully, these differences of opinion won't undermine their collective efforts to throw FPTP into the dustbin of history.

Approval Voting in its basic form is designed for single-member constituencies, but may be adapted into proportional approval votingWikipedia for multi-member constituencies (such as a Senate election).[12]

Comparisons with other voting systems[edit]

The good[edit]

  • One of the main advantages of Approval Voting is that it completely eliminates the “spoiler” and “centre-squeeze” effects that can occur in FPTP and IRV respectively,[13] and along with them, any incentive for the voter not to vote for their sincere favourite.[5][note 5] An additional candidate entering the race can only change the outcome of the election by winning it, and voters can approve their favourite candidate without any concern that this might help the greater-of-two-evils win. In other words, the system fulfils the monotonicity, participation and no favourite betrayal criteria.
  • A result of this freedom to vote for one's sincere favourite candidate is that every candidate's true level of support is reflected in the results, creating accurate and meaningful data on the population's political views. Under FPTP (and to a lesser extent IRV), support for candidates other than the two front-runners is artificially suppressed due to voters' fear of the “spoiler” and “centre-squeeze” effects.
  • Approval Voting is much simpler to understand than IRV for voters used to FPTP, as it does not involve multiple rounds or concerns about preferences.[14] Because of the simplicity of counting, the process that led to the outcome of an election would be more transparent for the voters.
  • Logistically, the system can be easily implemented on machines and ballot forms that were previously used for FPTP voting calculations, because the only change it requires is the allowance for voting for “one or more” candidates; this would save on the huge costs of designing and creating new machines.[15]
  • The rate of spoilt or invalid ballots would be even lower than for FPTP elections, because the ballot would still be valid no matter how many candidates the voter marks. It would be almost impossible for a voter to unintentionally spoil their ballot through genuine ignorance.[15]
  • The outcome of an election would provide valuable information on how popular a winning candidate is in absolute terms, with the winner's overall level of approval showing whether the voters adore them or simply dislike them the least. Neither the selection of a single candidate under FPTP, nor the ranking of candidates under IRV, provide any information on whether the voter actually likes or dislikes a candidate: all they can communicate is where the voter places the candidate relative to the other candidates.

Possible drawbacks[edit]

While Approval Voting is superior to FPTP in virtually every meaningful way, it has several features that may compare unfavourably with IRV, mainly due to the fact that it does not allow voters to differentiate between, or rank, candidates whom they may approve to varying degrees.

  • The voter is faced with the dilemma of where to define their “threshold of approval”: on one hand, approving of additional candidates beyond their favourite can sometimes undermine said favourite candidate's chances (in other words, failing the later-no-harm criterion), but on the other hand, withholding approval from non-favourite but tolerable candidates can hurt their chances against candidates whom the voter hates (and if everyone only approves their favourite, the system degenerates into FPTP.)[11] This problem is variously known as Burr's dilemma[16] or the chicken dilemma,[17] and while it is a drawback, at least it does not undermine the voter's incentive for approving their sincere favourite candidate – only their second- or third-favourite.[18] While the act of adding subsequent preferences cannot harm one's first preference under ranked voting methods such as IRV, it very much can help to elect someone whom the voter likes less than the candidate who would otherwise have won, which calls the value of the later-no-harm criterion into question.[19]
  • The lack of candidate rankings on the ballot can also feasibly create situations where a “least-disliked” candidate is elected over one who is the favourite of a majority of voters.[20]

Does it violate "one person, one vote"?[edit]

Absolutely not.[21][22][23] If a voter truly had more than one vote, this would mean they would be able to vote multiple times for their favourite candidate — something which Approval Voting obviously does not allow. Approving multiple candidates on the ballot does not mean having multiple votes: it means that the voter is casting a single vote that divides all the candidates into tiers of "approved" or "not approved".[7] Essentially, FPTP has the voter enact the same division of candidates into two tiers, with the (quite arbitrary) added restriction that every candidate except one must be placed in the lower ("not approved") tier.

If anything, it is FPTP that undermines the "one person, one vote" principle, considering that a voter undoubtedly has opinions on all the candidates, but is only permitted to record one of those on the ballot[24] — which means that the system could justifiably be described as "one person, a fraction of a vote". Furthermore, when FPTP elects a candidate with a plurality but a minority of votes, the majority of voters who voted against that candidate are left without a representative. These voters might have been okay with one or more of the other candidates who were not their first choice, but were not allowed to make this known on the ballot, so for them the system is effectively "one person, no vote".

See also[edit]

External links[edit]

Notes[edit]

  1. Score voting allows voters to give a numerical score to each candidate from a predetermined range (such as 0 to 10), with the winning candidate being the one with the highest average score.
  2. A cardinal voting system is one which allows the voter to evaluate each candidate independently of the others, without any restriction on how many candidates may be voted for, voted against, or given a certain score.
  3. The voting method for the survey was, funnily enough, Approval Voting. It is hard to imagine a different winner under a different voting system, however, as Approval Voting was the only method to achieve majority approval.
  4. Score then Automatic Runoff; a hybrid adaptation of Score voting in which the top two scoring candidates are treated to a runoff based on whichever of them is preferred to the other by more voters.
  5. To give an example of the “centre-squeeze” effect in IRV: out of three candidates (Left, Centre and Right), Centre (which should have the broadest approval) is eliminated in the first round because it has lost too many first-preference votes on both sides to the other two candidates, and Right then defeats Left in the second round. If some Left voters had instead voted Centre first, Centre would have survived the first round and then gone on to defeat Right, an outcome that Left voters would prefer.

References[edit]

  1. Score Voting. Center for Election Science.
  2. Claude Hillinger. The Case for Utilitarian Voting. Open Access LMU: Munich, 2005.
  3. J. F Laslier, ‘And the Loser is... Plurality Voting’. École Polytechnique, 2011.
  4. Mike Moen. Fargo Becomes First U.S. City to Try Approval Voting. Public News Service, June 10, 2020.
  5. 5.0 5.1 Kelsey Piper. This city just approved a new election system never tried before in America. Vox, November 15, 2018.
  6. Nathaniel Rakich. In St. Louis, Voters Will Get To Vote For As Many Candidates As They Want. FiveThirtyEight, March 1, 2021.
  7. 7.0 7.1 A paean to Approval voting – "Count all the votes". Center for Range Voting.
  8. Front page. Center for Range Voting.
  9. Other voting systems we advocate (under the right circumstances). Center for Range Voting.
  10. The Equal Vote Coalition.
  11. 11.0 11.1 Rob Richie. New Lessons from Problems with Approval Voting in Practice. FairVote, December 14, 2016.
  12. Clay Shentrup. Approval Voting Is Better Than Plurality Voting, Even In Multi-Winner Races. Medium, February 1, 2016.
  13. The Spoiler Effect. Center for Election Science.
  14. CGP Grey. Quick and Easy Voting for Normal People. YouTube.
  15. 15.0 15.1 Approval Voting vs. RCV. Center for Election Science.
  16. "Burr's dilemma" flaw in Approval voting system – Executive Summary. Center for Range Voting.
  17. Chicken dilemma. Electowiki.
  18. Primer. Simulating alternate voting systems. YouTube.
  19. "Later no harm" – an actually-silly (& massively overhyped by "FairVote") voting system criterion. Center for Range Voting.
  20. Approval Voting | Mathematics for the Liberal Arts. Lumen Learning.
  21. Approval Voting. Center for Election Science.
  22. BTernaryTau. The meaning of one person, one vote. GitHub, February 16, 2020.
  23. The David Pakman Show. Approval Voting: Better Than Ranked Choice?. YouTube.
  24. Mr. Beat. Why the Way We Vote Is Terrible. YouTube.