Tom, --- Tom Ruen <[EMAIL PROTECTED]> wrote: > I see there's two major conflicting principles that we want in a single > winner election winner: > 1. Plurality Principle - we want the winner who is can beat all others in > the full set of candidates. (Intensity of support) > 2. Condorcet Principle - we want a winner who can beat all other > head-to-head (Breadth of support)
I won't criticize your principles, but I think the two together would be hard to marry. #1 seems to be about the method's ability to focus voters on a small set of candidates, while #2, in my mind, is about the ability of voters to vote, and candidates to enter, without having to think so much about strategy. > Runoffs (with a majority winner constraint) are a sort of compromise between > these two principles. In the final round you know that the chosen winner > will also be the Condorcet winner for that final set of surviving > candidates. That's a nice little piece of knowledge. I don't understand this. How do we know the chosen winner is the CW for the final set? Are there only two candidates there? > For me this is the #1 feature of IRV which I think will cause politicians to > reject IRV. If I'm a candidate and I reach first or second in the first > round, I EXPECT I should NEVER have to face elimination except to be > defeated by a united majority against me. However IRV can have this result > in a race where second and third place are close. (Like A=39%, B=30%, C=28%, > D=3%) That's kind of an interesting principle. How about this: The first-round front-runner can never be eliminated. Other than that, IRV rules are used. If you privilege both of the first round's top two, you could end up with a "right vs. other right" scenario, where the left candidates don't have a chance, even if they have a majority. And that wouldn't really be much better than plurality, I don't think. > I call this general idea as: Respecting Plurality Order. This is what > candidates see in their expectations for success. (I accept that "plurality > order" is not a stable measure since it can change if you change the > original set of candidates, but there's nothing to be done about this except > completely abandon plurality counts as valuable.) > > I've never seen this "respect plurality order" idea expressed in this way, > but I find it useful - most of all to reject bottom-up IRV. I find it to be kind of a strange idea, since you don't seem to like the plurality method. If you like the fact that plurality encourages large first-preference scores, what could be so bad about it? What defense do you use when a method elects the plurality runner-up? > I often wonder that without any > spoiler effect, that candidates would too easily multiple beyond the ability > of voter to make an informed choice. I doubt this. I think voters will create their own spoiler effect, no matter the method, by not submitting complete rankings (particularly as the number of candidates increases). Also, I tend to think that whoever it is funding campaigns would feel pressure to get behind the most viable candidates. I could be wrong about that. > For me this also suggests a "progress" of methods from existing plurality > towards "spoiler free" Condorcet. And until the Condorcet pairwise process > becomes accepted legally as a valid counting method within "one person, one > vote", I see the best we can do is a Top-two Runoff. (OR Top-two Instant > Runoff) I think we should expect the non-instant runoff to multiply the number of candidates quite a bit. I was reading a book recently where the authors argued for plurality and against two-stage runoff for the reason that candidates don't have enough incentive to compromise before the first election. Kevin Venzke __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ---- Election-methods mailing list - see http://electorama.com/em for list info