On Mon, Jul 18, 2005 at 04:00:46PM +0200, Kevin Venzke wrote: > --- Stephen Turner <[EMAIL PROTECTED]> a écrit : > > (2) Among the criteria we usually discuss on this > > list, we do not have one on "stability", which should > > mean something like: "a small change in the ballots > > should change the outcome as rarely as possible". > > This seems desirable. Has it already been discussed > > somewhere? > > I think, if such a criterion came to be valued, it would result in > a lot of insensitive methods that behave more like Approval than any > ranked method. > > I'm lately interested in ranked methods with a strong approval > component, but I consider the insensitivity to be an annoyance > rather than a virtue: Why use a ranked ballot at all if additional > voters rarely make a splash? > > Kevin Venzke
I think stability is a very good property for a voting method to have, and I don't understand the logic that says stability means you don't want a ranked ballot. The point of stability is that it gives you more confidence that you've obtained a strong consensus, which seems to me to be a major goal of Condorcet methods. I've noticed that in practice MAM -- and the deterministic variant I developed for CIVS -- both seem to be much more stable than Schulze/beatpath winner, though I don't have a good argument for why this is. It seems that it's easier to upend the ordering by creating long, inobvious beatpaths than it is in MAM. -- Andrew ---- Election-methods mailing list - see http://electorama.com/em for list info
