Hello, --- Stephen Turner <[EMAIL PROTECTED]> a écrit : > This has raised two questions for me. > (1) Is it known whether there can exist a procedure in > which a pair (P1,P2) can never be reversed in the > social ordering by changing only the unrelated (P3,P4) > pairwise preferences in one or more ballots? > Dictatorship and anti-dictatorship obviously satisfy > this, but what about anything else?
This is ruled out by IIA, isn't it? > (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 ___________________________________________________________________________ Appel audio GRATUIT partout dans le monde avec le nouveau Yahoo! Messenger Téléchargez cette version sur http://fr.messenger.yahoo.com ---- Election-methods mailing list - see http://electorama.com/em for list info