On Sat, 2005-10-15 at 10:58 -0400, Warren Smith wrote: > I did not say voters always want full rankings. > > What I said was, I think there is a substantial SUBCLASS of elections, > in which, all voters (except perhaps for a few who are insane or writing > illegible ballots or something random like that) will want to provide full > rankings. > > If your voting method misbehaves badly commonly when confronted with > elections from within > that subclass, then it is not a good voting method. > > That was all I claimed. Now since I am asked for supporting evidence, I > respond > that many books and many authors, simply refuse to consider truncated ballots. > Also some countries make them illegal. I suggest to you, that much as you may > dislike this, there is a reason they did that, and it is not a good idea to > ignore it and pretend it does not exist when we design voting methods.
I agree with Warren that a system that doesn't break down in the face of full rankings is highly desirable, for many of the reasons that he cites. I think his argument could be reworded slightly to be less controversial. It's not that there's a universal or near-universal desire to provide full rankings. It's that there's a strong sense that asking voters to provide full rankings is the "right" (i.e. civically-minded) thing to do. A system that violates later-no-harm therefore has a serious political liability in that regard. You may disagree as to whether or not it's "right", but I think Warren presents a reasonable anecdotal case that there's widespread belief in full rankings (though I like others am interested in the specifics). My personal belief is that satisfying later-no-harm (or at least minimizing violation to rare instances) is highly desirable. I personally believe that getting people to think deeply about compromises is how we get to a more civil state in politics. If people can be jostled out of their comfort zone and consider the relative merits of candidates who they might at first blush consider "evil", then perhaps we'll truly get less evil candidates than the current batch who foment partisan rancor. Here's a related set of questions I've been meaning to ask: 1. Are the Later No Harm (LNH) criterion and the Sincere Favorite Criterion (SFC) mutually incompatible? 2. Are LNH and the Favorite Betrayal Criterion (FBC) mutually incompatible? 3. Are LNH, SFC and FBC mutually incompatible? If the answer to #3 is "no", I'm very interested in figuring out a system that satisfies those three. Rob p.s. can we please please please rename the "Sincere Favorite Criterion (SFC)" to "Majority Pairwise Winner criterion (MPW)" or something else more accurate? ---- election-methods mailing list - see http://electorama.com/em for list info
