Talk:Ranked Pairs

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[edit] capital letters

Dear Michael Hardy, you wrote: "Would the authors of articles on voting methods please stop worshipping capital letters with such incredibly fanatical intensity. It makes it hard to get links right."

I consider your recent changes to be vandalism. If you are really so upset about capital letters, then it is sufficient to replace e.g. [[Ranked Pairs]] by [[Ranked Pairs|ranked pairs]]. But the way you replaced capital letters destroyed the links completely. -- Markus Schulze 5 Jan 2005

[edit] Winning votes?

This article seems to define Ranked Pairs as using winning votes as the measure of defeat strength. Isn't that inaccurate, as far as what Tideman defined the method to be? KVenzke 17:42, May 22, 2005 (UTC)

  • Probably. The winning-votes variant should be mentioned in a section. RSpeer 05:25, May 23, 2005 (UTC)
It would be a tough choice since WV satisfies more criteria. The way the article is written now, anything that Schulze method satisfies is also satisfied by Ranked Pairs. But this will have to be qualified if this article defaults to margins. KVenzke 15:02, May 23, 2005 (UTC)

Tideman prefers margins at present, and has probably assumed that margins would be the defeat strength definition when publishing articles about ranked pairs, although he is open to the idea of WV. I think that it makes sense to present both ranked pairs/Tideman and beatpath/Schulze as base methods that can work with different definitions of defeat strength.Hermitage 23:23, 8 Jun 2005 (UTC)

[edit] MAM

I think that it is somewhat confusing for Steve to refer to his method as "MAM", rather than as a particular version of ranked pairs (which it is, essentially). I read the definition of MAM on his web site a year or so ago, and I had to ask on the EM list whether it was equivalent to RP. Thus, if MAM is discussed at all on wikipedia, I'd like for it to be made clear that it is a particular version of RP, or an alternate name for RP. Rather than bringing up MAM on wikipedia as a specific method, it might make more sense simply to discuss the component parts of MAM (i.e. the WV defeat strength definition and different tie breaker) as separate issues within the range of "ranked pairs" methods. However, if someone wants to briefly mention MAM in the article as an alternate name, I don't mind. Hermitage 23:35, 8 Jun 2005 (UTC)

F451 has deleted the MAM and MMV external links from this page. My personal opinion is that the links are appropriate, but I do not feel strongly enough to revert the edit. Hermitage 23:13, 13 Jun 2005 (UTC)

I'm conflicted. I definitely don't think MAM and MMV are significant enough to be mentioned in an article's text on Wikipedia; I think that the external links are perhaps the one place they should exist. But I don't feel strongly enough either. And I don't hold F451 at fault for anything here - if he makes an edit that's so non-controversial and keeps the articles clean, what's the problem? RSpeer 05:42, Jun 14, 2005 (UTC)

[edit] Voting criteria pass and fail

This article lacks an evaluation based on criteria. Since RP is a condorcet method, listing whether or not it satisfies the Smith criteria would be relevant. I wonder if there are any volunteers for this?--Fahrenheit451 00:29, 15 Jun 2005 (UTC)

Hmm, I guess we could just copy all the criteria over from Schulze method, since they'd be the same. But one note: If this article defaults to a margins interpretation (which I hope it doesn't, in fact), then the method won't satisfy Plurality criterion, Strong Defensive Strategy criterion, or Weak Defensive Strategy criterion. ...And I notice there is no article for Plurality criterion. Hmmmm. KVenzke 05:22, Jun 15, 2005 (UTC)

KVenzke, do you mean Majority criterion? - McCart42 (talk) 22:57, 16 July 2005 (UTC)
No, Plurality says that if A has more first preferences than B has votes of any rank, then B must not win with greater probability than A. Margins versions of RP and Schulze don't satisfy this. KVenzke 14:17, July 17, 2005 (UTC)

[edit] Ranked Pairs variants

Do the Ranked Pairs variants, Maximize Affirmed Majorities and Maximum majority voting, deserve their own article (especially given the amount of overlap due to the Tennessee voting example)? My vote is no. -- Dissident (Talk) 23:21, 25 December 2005 (UTC)

I agree. Maximize Affirmed Majorities (MAM) and Maximum majority voting (MMV) should be merged into Ranked Pairs, because MAM and MMV are only concreted formulations of Ranked Pairs. Markus Schulze 09:10, 26 December 2005 (UTC)
The merger is a good idea – especially if a comparison table of the variants is provided, similar to the one on Voting system. clacke 08:20, 21 April 2006 (UTC)

[edit] Weaknesses

Can anyone add a description of the weaknesses of this method? What kinds of strategic nomination / voting is it suceptible to? --P3d0 21:50, 6 January 2006 (UTC)

As with other Condorcet methods, strategic nomination and voting are possible when there's a Condorcet cycle, or when voters have enough information about the votes to create one. I don't know any strategic issues that are specific to Ranked Pairs.
A practical problem I've seen is that the method is not very deterministic. When ties between defeats occur, which is very likely in small elections, you have to break them randomly, and the entire outcome of the election can hinge on these ties. This is an observation from my use of the method, though, and I don't know of a source to cite for it.
rspeer / ɹəədsɹ 22:45, 6 January 2006 (UTC)
Isn't there a way to make a tie a tie? Why are tiebreakers necessary? --P3d0 16:29, 7 January 2006 (UTC)
But when you get a tie deep in the vote-counting process, not in the final result, what do you do with it? If you propagate the ties into the final result, you can get results like "((A > B > C > D) tied with (B > C > D > A)) tied with C > D > B > A". You'd be better off declaring the whole Condorcet cycle to be a tie - which in fact gives you a very theoretically nice method. rspeer / ɹəədsɹ 21:52, 7 January 2006 (UTC)

[edit] Broken link

The link in the Criteria section to the voting criteria table appears to be broken. It links an anchor on the Voting system page, but there does not appear to be any voting criteria table on that page. Qutezuce 08:56, 16 January 2006 (UTC)

I cleaned it up into the start of a more useful, self-contained section. Thanks! Scott Ritchie 22:07, 16 January 2006 (UTC)

[edit] Why the captial P in the title?

I ask this as a layman. -- nyenyec ☎ 16:11, 10 February 2007 (UTC)

Well, as you can see from the discussion above, voting theorists tend to capitalize everything, sometimes to the point of silliness. But the decapitalized title "Ranked pairs" doesn't seem right to me; it makes it sound like the article is about a kind of pairs, instead of about a voting system referred to by the name "Ranked Pairs". In comparison, the Borda count really can be described as a "count", as it's a way to count up votes. rspeer / ɹəədsɹ 11:03, 11 February 2007 (UTC)