Daniel, --- Daniel Bishop <[EMAIL PROTECTED]> a écrit : > Don't you mean half a vote for each candidate over every other? Of > course, if you're using margins, it doesn't make any difference. > > At least for single-winner Condorcet elections, I don't think it's > necessary to explicitly count X=Y as (0.5 X>Y + 0.5 Y>X) as long as they > are equivalent in the sense of > > * Pairwise Cancellation Criterion: If there is one ballot that ranks > X>Y, and another ballot that ranks Y>X, and both of these ballots are > changed to rank X=Y without affecting the relative ordering of any pair > of candidates other than {X, Y}, then the winner must not change.
Margins seems to satisfy this, but WV wouldn't. In particular, this could cause the loser of the X-Y contest to be elected instead of a third candidate. > It might also be a good idea to require: > > * Neutrality of Equal Rankings: The addition of one or more ballots that > rank X=Y will never change the winner from X to Y or vice-versa. This criterion seems extremely strong. There could be other candidates ranked on those ballots. Kevin Venzke Découvrez le nouveau Yahoo! Mail : 250 Mo d'espace de stockage pour vos mails ! Créez votre Yahoo! Mail sur http://fr.mail.yahoo.com/ ---- Election-methods mailing list - see http://electorama.com/em for list info