Talk:Plurality voting

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Isn't "two-round voting" much more common?

E.g., mayoral elections in Germany use it ... --User:Haraldmmueller 10:16, 18 September 2020 (UTC)

I don't think either one is much more common than the other. –Closed Limelike Curves (talk) 00:58, 22 February 2024 (UTC)

No mentioning of "election inversion" - why?

Similar question to Talk:First-past-the-post voting: Election inversion is a standard term; and a phenomenon mainly occurring with FPTP (albeit not only: Rounding procedures can produce them also in proportional systems). Why isn't this even mentioned here, let alone discussed - see of course 2000 and 2016 in the US (Michael Geruso, Dean Spears, Ishaana Talesara. 2019. "Inversions in US Presidential Elections: 1836-2016." NBER paper, slides by Nicholas R. Miller). It would nicely fit into the "wasted votes" section, because different amounts of "waste" for each selection directly imply the possibility of election inversion. --User:Haraldmmueller 08:20, 18 September 2020 (UTC)

It's not included because nobody's added it. Feel free to add it! Closed Limelike Curves (talk) 00:57, 22 February 2024 (UTC)

Similar articles

Plurality (voting) and this article seem to have same topic. Suggest merge. HudecEmil (talk) 19:36, 12 October 2022 (UTC)

Merge proposal

I am proposing Plurality (voting) be merged into Plurality voting. The articles have overlapping information and are about the same subject. Plurality voting is the longer article, is slightly higher quality, and receives more monthly pageviews (Plurality (voting) versus Plurality voting). -- Primium (talk) 17:45, 13 January 2024 (UTC)

@HudecEmil: Previously brought this up. -- Primium (talk) 17:50, 13 January 2024 (UTC)

@Primium the two topics are different, but the article you've linked is badly-named; I think we definitely don't want an article called "Plurality (voting)" that's different from "Plurality voting".

Plurality just means "the biggest share" (in British English, this is called a relative majority). It contrasts with a majority (in British English, an absolute majority), whch is a fraction bigger than 50%. Plurality (voting) could either be kept, turned into a Wiktionary entry, or merged into the majority page.

On the other hand, I just found out the page on first-past-the-post voting exists. That page is 100% a duplicate, since these are two names for the exact same system, and they need a merge. Closed Limelike Curves (talk) 02:32, 7 February 2024 (UTC)

Happy with a merge, but I think it should be to First-past-the-post voting (or simply First-past-the-post), which is the WP:COMMONNAME. Number 57 16:11, 24 February 2024 (UTC)

Google n-grams seems to suggest plurality is slightly more popular but I have no strong opinion on this. Closed Limelike Curves (talk) 03:15, 12 March 2024 (UTC)

Technically, there is a slight difference; first-past-the-post is the single-member version of plurality voting, which also includes multi-member versions. So merging into First-past-the-post doesn't make sense. Either merge into Plurality voting or shrink Plurality voting down to an overview of the different types of plurality voting, with a referral to First-past-the-post for a more detailed article on single-member plurality.174.67.226.163 (talk) 22:53, 9 March 2024 (UTC)

• Oppose

Just, I oppose it. It's just obvious why

Cheers, Arotparaarms (talk) 15:53, 28 February 2024 (UTC)

Oppose for reasons stated above: it is a distinct concept, and in particularly common use among political-science discussion in the USA (it's far more common of a term). A merge would add confusion, not remove it. Denzera (talk) 14:51, 12 March 2024 (UTC)

Oh, I also oppose it but I didn't have a concrete reason, so I guess I now have a solid reason, and it's interesting how it's a common term across the globe. Arotparaarms (talk) 15:38, 12 March 2024 (UTC)

Moved to Talk:Plurality voting § Merge from FPTP

• Oops, the wrong section. Thank you. Will move. Викидим (talk) 17:31, 13 April 2024 (UTC)

Merge from FPTP

FPTP and Plurality are the same system. FPTP should be merged into this article with a redirect. Closed Limelike Curves (talk) 17:21, 12 March 2024 (UTC)

• Oppose FPTP is a particular case of plurality (and the most popular). What we need is to rewrite the lead to reflect this fact. --Викидим (talk) 06:18, 13 April 2024 (UTC)

  1. This is asking about whether plurality (voting) should be merged with Plurality voting (which are two completely different things).
  2. FPTP and plurality are synonyms.

  Closed Limelike Curves (talk) 17:23, 13 April 2024 (UTC)

  Many authors would disagree with your #2. Plurality voting, in many sources at least, includes such non-FPTP systems as two-round system and alternative vote. Викидим (talk) 17:41, 13 April 2024 (UTC)

  I'd like to see a source for that, because I've never seen any of those systems called "plurality", but if correct, everything in this article would need to be merged into FPTP and this article rewritten from scratch (because it only talks about FPTP right now). –Maximum Limelihood Estimator 17:43, 13 April 2024 (UTC)

  In general FPTP = SMP (single-member plurality a.k.a. simple plurality). I can point to Maurice Duverger of the Duverger Law fame. A brief summary of his beliefs can be found in not-very-authoritative source here: [1] on p. 331 ("Plurality system with additional conditions"). Sorry, I do not have Duverger's book handy and cannot check his terminology immediately. This is not the only PoV; many authors use FPTP and plurality system synonymously and drop the single-member/simple qualifiers - but many retain them. Викидим (talk) 18:25, 13 April 2024 (UTC)

A brief summary of his beliefs can be found in not-very-authoritative source here: [1] on p. 331 ("Plurality system with additional conditions"). Sorry, I do not have Duverger's book handy and cannot check his terminology immediately.

1. The text doesn't seem to quote Duverger himself directly, it just talks about Duverger's law.
2. The text is, as mentioned, a not-very-authoritative source.
3. The text also seems to be confusing the use of a single non-transferable vote in the first round of a runoff (which can arguably be called "plurality voting") with the two-round runoff as a whole, which is not a kind of plurality voting.

This is not the only PoV; many authors use FPTP and plurality system synonymously and drop the single-member/simple qualifiers—but many retain them.

The synonymous usage seems to be by far the more common use in social choice theory. With regards to the other two terms you mentioned:

• "Single-member" means the combination of plurality with single-member districts, i.e. local elections. The term "single-member" is used to distinguish plurality voting from its multi-member (multi-winner) variant, called SNTV.
• "Simple plurality" has the same meaning as in "simple majority" (which means a majority, ignoring abstentions). In other words, it's a plurality of votes, ignoring abstentions: if the largest number of votes is for "abstain", this option is ignored, rather than leading to a do-over election. –Maximum Limelihood Estimator 15:37, 15 April 2024 (UTC)

IMHO for authors that consider plurality synonymous with FPTP, the qualifiers "single-member", "simple" would be excessive and unnecessary, their very use underscores that differences do exist. SNTV seems to me like one more plurality system. Викидим (talk) 19:09, 15 April 2024 (UTC)

SNTV is one of several minor variants of FPTP/Plurality, yes, which is why it has a separate article. But as the article itself says in the opening, SNTV is a kind of FPTP.

IMHO for authors that consider plurality synonymous with FPTP, the qualifiers "single-member", "simple" would be excessive and unnecessary,

Yes, they would be, because this is how everyone understands the term "Plurality"! If the term was this ambiguous, nobody would use it; they'd just say FPTP. As mentioned, the current article says nothing about these other systems, because nobody uses the term plurality like this.

In all my years reading the social choice literature I have never seen anyone use "plurality" to mean "instant-runoff voting", and the source you provided is at best ambiguous as to whether it's even doing that. –Maximum Limelihood Estimator 19:54, 15 April 2024 (UTC)

I can easily agree with you on instant runoff. For the purposes of this discussion, it is enough to establish that FPTP and "plurality" are not the same thing (SNTV does that), and I am way out of my depth to provide any suggestions on where the evolution of Plurality voting should go. Викидим (talk) 19:58, 15 April 2024 (UTC)

For the purposes of this discussion, it is enough to establish that FPTP and "plurality" are not the same thing (SNTV does that),

OK, so how about :

1. Redirecting "FPTP" to "Plurality" (which is the most common use), and then

2. Putting up a "For the multi-winner variant of plurality, see SNTV".

I am way out of my depth to provide any suggestions on where the evolution of Plurality voting should go.

That's fair. –Maximum Limelihood Estimator 20:05, 15 April 2024 (UTC)

I am no expert on the issue. However, (1) FPTP is a colloquial, but very well-known - and easy to understand - term. Few people would understand the plurality correctly. Correspondingly, the sheer volume of information on FPTP is much larger than that on other forms of plurality combined. So, if redirecting, it would be expedient and historically correct, to go other way, explaining the non-FPTP plurality as a deviation from (or an improvement of) the simple one. (2) I do not think this would be the best approach. Instead, this article can become an overview of the voting systems that are rightly or wrongly described as plurality systems, with a list of actual use. (3) The main dichotomy, IMO, is between the proportional / plurality systems, and this might be a good place to expound on their differences. Викидим (talk) 20:46, 15 April 2024 (UTC)

So, I checked on Google Scholar to be extremely sure. Of the first 20 hits for "plurality voting", 19 were about first-past-the-post in a single-winner context, and one was a false positive (it picked up "plural voting" instead of "plurality voting").

To make sure this wasn't just a technical term, I googled "plurality voting". I took the first 5 reliable sources I came across. (I judged one source unreliable, but it agreed as well). Of those 5 pages, 4 defined plurality voting as a single-winner election method (i.e. defined it as FPTP), those being Britannica, Ballotpedia, and two pages from Moravian and Georgetown universities. The 5th was this page. –Sincerely, A Lime 21:58, 13 May 2024 (UTC)

• Agree, Oppose Arotparaarms (talk) 22:42, 13 April 2024 (UTC)

Opppose

Plurality voting is a broader concept, which includes:

- SNTV - a multi winner system with very different results than FPTP

- bloc voting, general ticket, the multi-winner version with similar effects. Because of it's widespread use, FPTP deserves a seperate article which doesn't include these

- limited voting, approval voting (of course, not PAV, and of course, even single winner is not often called plurality voting since it would be confusing)

it is important to contrast plurality voting to:

-majority voting - usually IRV and TRS would be considered so as they have the principle of having next rounds if there is no majority. otherwise, majority and plurality are similar rules, so highlight that not everywhere they have the same linguistic usage - "relative/absolute/simple majority/plurality

-proportional representation, completely different principle Rankedchoicevoter (talk) 07:08, 19 April 2024 (UTC)

That said, if you're right, we'll need to merge this page into FPTP instead of the other way around, and then turn this page into a disambiguation directing people to choose SNTV or FPTP. –Maximum Limelihood Estimator 16:39, 24 April 2024 (UTC)

@Rankedchoicevoter the term "Majority voting" in social choice theory has a much more restrictive meaning (see Condorcet winner criterion, often called majority-rule in the social choice/voting theory/welfare economics literature). IRV and two-round would be considered to fall under the sequential-loser or core support umbrella instead, alongside plurality.

Approval voting would never be considered a variant on plurality voting. (On the other hand, TRS might actually be counted as a variant of FPP/Plurality.)

"Plurality" without qualification excludes all the systems you mentioned. FPTP also includes SNTV (the proportional-representation form of FPTP). The phrases FPTP and Plurality voting are synonymous. –Maximum Limelihood Estimator 23:29, 23 April 2024 (UTC)

Terminology sources

Trying to list the works that can be used as references for terminology. Feel free to expand or object.

• Ross, James F. S. (1955). "Preface". Voting in Democracies. A Study of Majority and Proportional Electoral Systems. Faber & Faber. Retrieved 2024-04-24. Recommended in [2]

Викидим (talk) 01:54, 24 April 2024 (UTC)

It looks like Rosen (1974) says:

Bloc voting and plurality voting are, respectively, the multi-member and single-member forms of the first-past-the-post class of systems.

Nice source, I like it :) –Sincerely, A Lime 21:45, 13 May 2024 (UTC)

Good. I have no deep knowledge, so any agreement on the sources would work for me. It is clear to me by now that the terminology varies across the researchers; this is not an unusual situation for many fields of study. We can simply accept someone's terminology (with attribution), and mention other versions. Ideally, we should find a source that acknowledges the differences and attributes them to particular researchers. While writing Zigzag Moderne (about an architectural style the very existence of which is debated), I was lucky to have such a source. Let's hope we can find one here, too. Викидим (talk) 23:32, 13 May 2024 (UTC)

That sounds like the other way way around. Plurality voting is the general type, bloc voting a multi-member version. I added sources in the article supporting that view. I am aware of the wide range of use for these terms and when it gets more rigorous, these have to be clarified, but first-past-the-post is same as SMP, and it would add additional confusion to say otherwise (it's in the name "first", at least that part makes sense, even if there is no post...). Rankedchoicevoter (talk) 09:07, 14 May 2024 (UTC)

As I have said, I am OK with any arrangement that would state something like "X defines PV as a subset of FPTP[cite]" (or the reverse). It seems to me that there is no consistency here, so we need to attribute the definitions. Викидим (talk) 09:39, 14 May 2024 (UTC)

"First" can also just mean the beginning of a list, e.g. "the first 100 people to sign up will receive a discount".

FWIW, I agree that I don't like the use of the term "FPTP" as including SNTV; if I wanted to say SNTV, I'd say SNTV. It seems like the vast majority of papers nowadays use "Plurality" and "FPTP" interchangeably, but some older sources try to maintain a distinction; but this is inconsistent. –Sincerely, A Lime 20:44, 14 May 2024 (UTC)

If this is the case, we need to reflect it. It would be great to find a source that reflects this change. Викидим (talk) 00:15, 15 May 2024 (UTC)

A good example of people using "Plurality" quite differently from how most people use it today is Merrill and Nagel 1987, who use it to mean any voting rule that elects the candidate(s) with the highest score(s). (Which makes ~no sense to me, because every voting rule does that.) –Sincerely, A Lime 02:18, 26 May 2024 (UTC)

(From what I can tell everyone else agrees, because I was unable to find any other papers using this meaning.) –Sincerely, A Lime 02:19, 26 May 2024 (UTC)

It makes perfect sense to me. The proportional voting does not elect candidates with most of the votes, it elects a particular number of representatives from party lists, while parties decide themselves (ahead of the elections) who the representatives will be. Merrill and Nagel are not alone in the main (top-level) classification split being proportional vs. plurality. These researchers treat plurality a a generic case, with further details like FPTP vs. multi-candidate districts. Викидим (talk) 03:36, 26 May 2024 (UTC)

Well, the thing is, you can define proportional representation as being plurality rules in that sense too... see highest averages method: Seats are awarded to the candidate with the highest value of ${\frac {\text{votes}}{\text{seats}}}$ (or a slightly different ratio for different divisor methods).

No matter what you do, it's still a "plurality" rule :)

I think it's supposed to contrast with a majority in the sense that, if no candidate wins a majority, there is no winner. Balloting continues until a candidate achieves a majority. Most parliamentary officers are elected this way (e.g. the Speaker of the House). –Sincerely, A Lime 04:00, 26 May 2024 (UTC)

All I am trying to say is that a significant number of researchers appear to split the voting methods into two broad groups: proportional vs. plurality, with further subdivision happening on the inside of these two classes. Whether they are right or wrong is immaterial, IMHO: we simply need to reflect this PoV (part of the mainstream) somewhere. To me, this article is a convenient place to do so: if some expert takes an opinion that "plurality" is a synonym of FPTP, we can mention their position here and write down the details in the FPTP article. If, however, an expert thinks that plurality is the opposite of proportionality, their opinion belongs here. Викидим (talk) 04:56, 26 May 2024 (UTC)

Right, what I'm saying is I don't think any expert defines "plurality" as just meaning "not proportional".

In any case I'd give this glossary as a decent citation (where it defines "plurality" to mean FPTP).

http://ndl.ethernet.edu.et/bitstream/123456789/77460/1/21.pdf#page=138 –Sincerely, A Lime 16:51, 28 May 2024 (UTC)

(1) I am happy with this text. (2) However, it also says that the multiple-candidates election is also plurality, so plurality is not equal to FPTP. (3) There are plenty of sources that are published in peer-review journals and books from reputed publishers that contain very clear language of opposition between PR and PV, like "plurality vs proportional", etc. (4) Therefore, there is no single definition that we can present to the reader, IMHO. Ideally, it would be great to find a review of contradictions in definitions. Викидим (talk) 18:12, 28 May 2024 (UTC)

Here is one of these sources with very clear language: [3] on page 3. Викидим (talk) 18:14, 28 May 2024 (UTC)

Interesting, thanks. I'd never seen that before. I think this explains the disagreement and confusion:

1. Some (particularly older) sources, mostly in political science, define "plurality voting" to mean winner-take-all representation.

2. Other (especially newer) sources, including most of social choice, define "plurality" as an abbreviation of the term first-preference plurality.

In that case, is it reasonable to make "plurality voting" a disambiguation page that explains these two common meanings? cc @Rankedchoicevoter Closed Limelike Curves (talk) 18:43, 14 June 2024 (UTC)

My goal here is twofold:

1. I am sure there is a conflict of definitions even in the expert literature. We need to reflect this conflict in our encyclopedia, so the readers can understand better both other articles in Wikipedia and the external literature
2. In order to achieve #1, we should not merge plurality and FPTP, IMHO

Викидим (talk) 00:48, 15 June 2024 (UTC)