Talk:Ranked Robin: Difference between revisions
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:::: [[User:Kristomun|Kristomun]] says: "''Ranked Robin uses ordinal ballots, so it can't be Score''". As I read through the description of [[Ranked Robin]] more closely, I see there's a lot that I don't understand about the proposal. As written, it describes a "ranked ballot" (where "1" is at the top) but it seems possible to use a [[STAR voting]]-style ballot (the way my old [[electowidget]] voting mechanism worked). That said, as a drop-in replacement for [[instant-runoff voting]], this seems fine, and moreover, it seems to me that cycles will be rare in practice, so the [[Copeland's method|Copeland set]] seems likely to only have one winning candidate in 99.9% of the cases. Regardless, since the system uses pairwise matrices (like most Condorcet methods do), it's hard to see how this method has much in common with Borda, since adding candidates to the bottom of the ranking shouldn't make any difference in the pairwise comparison between the candidates above the newly added candidate.-- [[User:RobLa|RobLa]] ([[User talk:RobLa|talk]]) 04:46, 13 January 2022 (UTC)
::::: True, if the 99.9% Condorcet rate is a fundamental fact, then it doesn't much matter what Condorcet completion rule you use. It is possible that it's a side effect of the two and a half party domination that IRV encourages, though, or the two-party domination that using Plurality everywhere else does.
::::: I'd probably say the two main drawbacks of Ranked Robin are that it's more susceptible to strategy (than say minmax), and that it's not actually cloneproof. OTOH, Borda's honest VSE is not all that shabby, so at least you're getting ''something'' in return :-)
::::: As for Condorcet and Borda, there's a definite link between the two. Suppose there are no truncated or equal-rank ballots. Then the sum of A>X over all X is A's Borda score, so you can do a Borda count by using the pairwise matrix. That's what makes methods like Smith//Borda summable. Adding another candidate adds another X where A>X can be added to A's sum. In a more general sense, Borda is the "mean" while Condorcet is the "median": see http://lists.electorama.com/pipermail/election-methods-electorama.com/2011-January/092327.html. This gives a good intuition of why Borda is more strategically susceptible: because the median is robust and the mean isn't. [[User:Kristomun|Kristomun]] ([[User talk:Kristomun|talk]]) 10:26, 13 January 2022 (UTC)
== Clone dependence ==
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