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What's the origin of the name Condorcet? Ben Finn 14:13, 10 December 2005 (UTC)
The link to "minmax" goes to the wrong article.
The following statements are taken from this article:
"The Condorcet candidate or Condorcet winner of an election is the candidate who, when compared in turn with each of the other candidates, is preferred over the other candidate."
"Non-ranking methods such as plurality and approval cannot comply with the Condorcet criterion because they do not allow each voter to fully specify their preferences."
In a FPTP/plurality system, the voter specifies their preference for one candidate. The FPTP winner therefore has more votes than each other candidate in turn.
Therefore, on face value, FPTP does have condorcet winners - the second above statement is false. If it is assumed that there will always be an element of tactical voting and we therefore cannot see who the voter really would have voted for absent tactics, then this article should state this. The second statement above, however, states that FPTP does not allow each voter to fully specify their preference - and at face value this statement is false: there is one candidate to be elected, and the elector is allowed to vote for one candidate.
This article needs a re-write so that it says what is means to say, but at the moment it is a nonsense.
A further question arises, separate from the above points, in that if one is allowed to say that FPTP is not condorcet due to the tactical voting issue, then no voting system can be condorcet. Even if a specifies from 1 to 10 their order of preference of a candidate list with 10 people, then that voter still may be voting tactically. Therefore there can never be a strict logical criterion of condorcety, although it is of course possible to devise such a criterion is one introduces subjective areas of greyness in the definition.
Thoughts ?--jrleighton 04:23, 6 January 2006 (UTC)
In the article Majority alternative (see this version) the following text appeared:
This text was unsourced, except possibly for the works listed in "Further reading" (Black, D.: The Theory of Committees and Elections, Cambridge 1958; Farquarson, R.: Theory of Voting. Oxford 1969; and Sen, A.K.: Collective Choice and Social Welfare. San Francisco 1970.) and it is unclear to what extent in may be Original Research. It is also unclear to what extent voters in real-world elections have the tools to form broad coalitions and engage in the kind of negotiations implied above -- it is clear that agreements to participate in a coalition are generally not enforceable, and are, in at least some jurisdictions, illegal.
If it can be attributed to a reliable source this text should be incorporated (in some form) into this article. Anyone knowing of such a source is requested to provide it here. DES (talk) 21:01, 22 June 2007 (UTC)
Perhaps, this is a reliable source: Wesche, E.: Die "unsichtbare Hand" in der Demokratie. Zur normativen Rechtfertigung von Abstimmungsverfahren. (The "invisible hand" in Democracy. About the normative justification of voting systems) in: Göhler, G. (Hg.): Politische Theorie. Klett-Cotta Verlag Stuttgart 1978.
I don't know of any other source for the respective theorem nor was there any refutation.
In any case the given proof is simple. The theorem can be falsified by any counterexample. Eberhard Wesche 17:59, 25 June 2007 (UTC)
Some remarks about the existing article „Condorcet criterion“.
The synonym to “majority alternative” is “Condorcet winner” not “Condorcet criterion”. Therefore it is difficult to merge both articles.
The term “majority candidate” was already used by Duncan Black.
It is written: “The Condorcet criterion for a voting system is that it chooses the Condorcet winner when one exists.”
How does the voting system “choose” the outcome? This is not explained. I guess it is assumed that each voter votes strictly according to his preferences.
This assumption is rarely fulfilled. Nobody wants to waste his vote by voting for an alternative with no chance to be the winner.
In any case voting “sincerely” is not the only possible model of voting behaviour. This the reader should know whenever a "criterion" is introduced.
If one assumes full information and unrestricted agreements of how to vote, an existing Condorcet winner will be the outcome even with plurality voting, which does not fulfill the Condorcet criterion. Eberhard Wesche 18:57, 25 June 2007 (UTC)
The definition of "Condorcet criterion" should make it clear that a Condorcet winner obtains a majority of votes against every other candidate. Condorcet methods thus belong to the class of majority voting rules. For instance, the current definition does not exclude the notion that a Condorcet winner must obtain, say, unanimous agreement against every other candidate.-- Jsorens 15:50, 28 September 2007 (UTC)
Given the prominent place this page has in Template:Electoral systems, shouldn't this page have something on the criticisms (and strengths) of the Condorcet criterion? Peter Ballard ( talk) 11:49, 27 December 2007 (UTC)
Well, I'm not sure there is any reliable source on such. However, we could open a controversies section. In such, it's enough, I'd claim, that there is notable *argument* on a point, and the arguments should be attributed. Notability is a bit tricky to define here. However, outside of the article itself, I could certainly write about a defect of the Condorcet criterion. It is similar to the defect in the majority criterion; that is, preference strength is not considered, any preference, no matter how small, can create a Condorcet winner. The example I give is the pizza election. Three friends, election methods aficionados, want to choose a pizza; for some reason they can only buy one variety. Is it Pepperoni, Mushroom, or Anchovy? Two of the friends have a very slight preference for Pepperoni, but Mushroom is almost as good, they really don't care much. Turns out that everyone dislikes Anchovy. But one has a religious problem with the pork in pepperoni. What is the best election outcome, and what election methods will reveal it? Any majority criterion or Condorcet criterion satisfying method must choose Pepperoni. Range voting with sincere votes will choose Mushroom, as will Approval voting likewise. The debate over these methods is pretty silly except in contentious environments, where it is expected that there may be significant strategic voting. For example, the Pepperoni voters could decide not to vote for Mushroom. But, in fact, this contradicts the assumption that they really don't care much. Essentially, what is controversial is the behavior of methods that consider preference strength under conditions of strategic voting. Not with sincere votes. However, this is Original Research, probably. There may be something published about Approval on this point; Range is pretty new in the field of election methods.
I've found this in a number of areas in the field of voting systems: there may be a method which has been around, even for centuries, and yet nobody studies it and the election criteria are designed as if the method does not exist. Approval was used for five hundred years in Venice to choose the Doge, it was used for quite a few centuries to choose Popes. A great deal is written about the supposed inherent contradictions in representative democracy as if the institution of the proxy did not exist, and so on.
The Condorcet Criterion satisfies a very important intuition, and the problem with it is only related to single-ballot election methods where there is insufficient mutual knowledge. With fully-informed voters, there is no problem with the Pizza election, for the majority will, assuming it cares about the society of friends, change its opinion and the vote will be unanimous. Plurality works fine! Indeed, democratic process is founded on binary votes, Yes/No, majority necessary for a decision to be made. Standard democratic process used for election by ordinary motion is Condorcet-compliant, in the hands of informed members. It is, in fact, obvious. But can we find any reliable source for that? I'd be fascinated to know, for this fact is my own original research, I read it nowhere. We can, if we want, *create* reliable source, it's not difficult if anyone cares (and if the thesis is accepted by the process, that is, it does pass peer review. Consider Usenet, Mr. Ballard, or a mailing list of election methods people, add only a membership and voting process, plus a "publisher" who uses that for the editorial process. Google the "Election Methods Interest Group" for one possible path that could lead to this. -- Abd ( talk) 02:44, 31 December 2007 (UTC)
(unindent) Sure. However, I've got other fish to fry. I made one change, but it's an example that anyone can verify, so it does not require sourcing. Nevertheless, if Mr. Ballard thinks any information in the article requires sourcing, he's welcome to add a citation needed tag, and anyone, including him, could do the research. The article currently, with an exception that I removed, consists, as far as I noticed, of well-known facts. What is needs most of all is not sources, but analysis of the significance of the criterion, which *will* require sources, to be sure. They certainly exist, it is merely work to find them, then edit the article to show the analysis, and cite the sources. Be our guest, Mr. Ballard. -- Abd ( talk) 04:17, 2 January 2008 (UTC)
(unindent) One the things of condorcet criteria, that someone may see as a bad thing is that the pairwise comparisons are made using first past the post (or approval method if you allow equal rankings), range voting is way better than first past the post even with two candidates. Actually range voting pass Condorcet criteria when you use range voting to decide the winner of the pairwise comparisons. 177.92.128.62 ( talk) 11:24, 10 January 2019 (UTC)
Given that Llull winner redirects here, I'm assuming that a Llull winner is a candidate who wins according to the Condorcet criterion, but can someone confirm this for me, and if so, mention this in the article? Thanks. Jason A. Recliner ( talk) 14:01, 14 August 2008 (UTC)
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Should Condorcet criteria apply to three or more candidates? The article says two-candidate. If there are only two condidate, why bother with Condorcet? aai'm not trying to start a new topic. Only get a clarification of the original. If I try to preview, I get timed out. I have a vandalism charge showing on one attempt. DickBoyd 2/21/12
I think it is unfortunate that the Condorcet method is conflated with its various circular tiebreakers.
In other words, think of elections where there actually are Condorcet Winners. I believe that these elections are not in violation of IIAC or Arrow's Impossibility Theorem.
From what I remember of my studies, only the elections with no Condorcet Winners, and which seek to award a winner anyway, are the ones that fall afoul of these criteria. I am less sure about the other three mentioned criteria, but the same might be true in those cases as well.
The problem is that the only Condorcet methods that are discussed in these wikipedia pages are the ones that seek to award a winner even when there is no Condorcet Winner. If you think of every Condorcet method as a section of logic that finds a Smith set (I believe all are Smith-efficient), and then a "tiebreaker" section of logic that awards the winner from the Smith set, the distinction is not made that it is the tiebreaker methods that are problematic, and not the principle of finding a Condorcet winner. By definition, tiebreaker methods do not always find a Condorcet winner, because in those cases, the Condorcet winner does not exist.
I realize that the point of elections are to award a winner, but I think there is utility in pointing out that these criterion problems might only be relevant for the elections where there is no Condorcet Winner. — Preceding unsigned comment added by Tunesmith ( talk • contribs) 05:07, 29 May 2012 (UTC)
Greetings,
I tried to edit this article and correct the false statement arguing that the Condorcet criterion is not compatible with the consistency criterion, quoting the works from H.P. Young and A. Levenglick in their paper "A Consistent Extension of Condorcet's Election Principle" (1978). The corrections have been canceled, arguing the definition of the consistency criterion is different in their work than the usual admitted definition.
As to avoid an "editing war", I'm posting here to discuss the matter.
On Wikipedia, the consistency criterion is defined as follows : "A voting system is consistent if, when the electorate is divided arbitrarily into two (or more) parts and separate elections in each part result in the same choice being selected, an election of the entire electorate also selects that alternative."
Quoting H.P. Young and A. Levenglick, the definition of the consistency criterion : "If two committees meeting separately arrive at the same consensus ordering, then meeting together this should still be their consensus".
Aside from the fact that H.P. Young and A. Levenglick only consider exactly two parts of the electorate in their definition, which has no impact on it as it is arguably trivial to prove it can be generalized, there is no difference in the definition of the consistency criterion. In the same paper, they also showed the Condorcet's criterion and the consistency criterion are compatible, as they even showed a unique method checks three properties, including these last two.
Maybe I'm wrong, but I'd like to know how, then. Thanks. 192.196.142.26 ( talk) 15:18, 17 March 2014 (UTC)
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I think this sentence is incoherent: "When voters identify candidates on a left-to-right axis and always prefer candidates closer to themselves, a Condorcet winner always exists." What does it mean to "prefer a candidate closer to [one]self"? Where is that defined? Is there an alternate expression of this idea that does not require the use of an undefined notion? — Preceding unsigned comment added by Wdowling ( talk • contribs) 18:33, 4 August 2014 (UTC)
I think these two sentences are contradictory: "For a set of candidates, the Condorcet winner is always the same regardless of the voting system in question. A voting system satisfies the Condorcet criterion (English pronunciation: /kɒndɔːrˈseɪ/) if it always chooses the Condorcet winner when one exists." The latter sentence implies there are systems which do not satisfy the Condorcet criterion, while the first states there are no such systems. Philgoetz ( talk) 22:43, 20 November 2016 (UTC)
In pluralistic head-to-head elections, you would get
Followed by nothing. — Preceding unsigned comment added by 203.87.133.147 ( talk) 09:34, 17 June 2016 (UTC)
Agreed. In fact, that is immediately followed by a second incompleteness:
"Range voting satisfies the Condorcet criterion as long as voters score candidates in the head-to-head elections as they do in the full election.[5] For example, let's say three voters vote for three candidates (A,B,C) as follows:
<missing details on how the voters vote>
The second candidate is the Condorcet winner ..."
I'd love to see this completed, because range voting strikes me as the perfect mechanism for maximizing the satisfaction of an electorate, and I am trying to understand the significance of the objections to it. — Preceding unsigned comment added by AmigoNico ( talk • contribs) 02:48, 3 September 2016 (UTC)
AmigoNico ( talk) 02:50, 3 September 2016 (UTC)
You're right that there's a problem with the page; here's an example of Range Voting's Condorcet failure. Suppose there's a two candidate election with candidates A and B, and voters rate candidates on a scale from 1 to 10. There are three voters and the ballots rate the candidates thusly: (A:6, B:1), (A:5, B: 2), (A:1, B:10). The total scores are A:12 and B:13, making B the winner even though a majority of voters strictly preferred A over B.
Range voting often looks very attractive in terms of the formal criteria it satisfies, but its ability to satisfy many of these criteria is complicated by various arguably unrealistic assumptions about voter behavior.
For example, range voting strongly incentivizes a form of tactical voting in which voters give a maximum possible rating to options they most prefer and the minimum possible ranking to other options. If this behavior is typical, then range voting degenerates into approval voting. SoapstoneTurtle ( talk) 03:20, 3 September 2016 (UTC)
The article states this: The Condorcet criterion implies the majority criterion; that is, any system that satisfies the former will satisfy the latter. Because of this, Arrow's impossibility theorem shows that any method which satisfies the Condorcet criterion will not satisfy independence of irrelevant alternatives.
In the first place, it's not at all obvious what the second statement about IIA has to do with the majority criterion.
In the second place (and this is the major point), I don't see how the Condorcet criterion conflicts with IIA. Arrow's Impossibility Theorem does not address the Condorcet criterion. In fact, IIA would seem to me to imply the Condorcet criterion rather than conflict with it, since starting with any two-candidate election in which the Condorcet winner trivially wins and then adding other candidates who cannot pairwise beat the winner should not change the winner under IIA. If I'm wrong about this, can some explanatory language or references be added to justify these assertions? SoapstoneTurtle ( talk) 03:20, 3 September 2016 (UTC)
Well, as written the article is wrong because it ignores the possibility of a dictator. It also assumes unrestricted domain (which seems like a more reasonable assumption). I think it's clear what was meant though. Arrow's Impossibility Theorem does not address the Condorcet criterion but it does address the majority criterion, which is implied by the Condorcet criterion. Therefore Condorcet is incompatible with IIA (ignoring the other two "outs" of Arrow's Theorem). 73.241.142.127 ( talk) 06:08, 23 September 2016 (UTC)
A Condorcet method is any method that satisfies the Condorcet criterion. There is no reason to discuss the methods collectively in a separate article from the criterion. Currently the Condorcet criterion article consists mainly of brief synopses of some of the methods which fail to satisfy the criterion. The little other information is duplicated in the current Condorcet method article. There is no such thing as "the Condorcet method". A previous merge discussion in 2004 petered out despite only one user ( Daelin) expressing any reluctance to merge jnestorius( talk) 13:47, 6 November 2017 (UTC)
The result of the move request was: Moved ( non-admin closure) ( t · c) buidhe 15:41, 12 February 2021 (UTC)
Condorcet criterion → Condorcet winner criterion – This article is already the target of the Condorcet winner redirect. The Condorcet loser criterion is different than the "Condorcet criterion", so having a generically named criterion can be confusing. Could we help make things a little clearer by renaming this article Condorcet winner criterion? If nothing else, the distinction from the Condorcet loser criterion should be better explained in this article. RobLa ( talk) 13:16, 5 February 2021 (UTC)
In a recent change, @ HudecEmil: claims that Coombs' method always selects the Condorcet winner, citing this paper:
Coombs rule — Grofman, Bernard, and Scott L. Feld (2004) "If you like the alternative vote (a.k.a. the instant runoff), then you ought to know about the Coombs rule," Electoral Studies 23:641-59.
The paper is incorrect. There are plenty of citations that claim that Coombs does not always select the Condorcet winner, but I'll cite one:
There's an example given in the Felsenthal and Tideman paper that shows an example of Coombs selecting someone other than the Condorcet winner. I'll be reverting the claim that Coombs complies with the Condorcet-winner criterion. -- RobLa ( talk) 05:11, 20 October 2022 (UTC)