On Dec 20, 2007, at 11:59 PM, rob brown wrote: > And all I wanted to know was, can we agree that we can be "always > fair" in a case where there are only two candidates? > > My understanding is that Arrow believed that a two candidate election > was trivially solvable, by a simple majority vote. > > Meanwhile, I believe the general opinion of those who advocate Range > Voting is that it is NOT solvable, because Range Voting people are > after a different sort of fairness than what Arrow was after.
Arrow doesn't talk about 'fairness' per se, but rather a collection of explicit criteria. The problem with two-candidate elections is 'agenda manipulation': How did there get to be only two candidates? The US presidential election is a fine example of agenda manipulation, in which many factors (attractiveness to donors, party machinery, restrictive ballot access laws) other than voter preference goes into deciding, say, that of all eligible candidates, only John Kerry and George W Bush will (effectively) be on the ballot. So in that sense, you're certainly right to question the guarantee of fairness, regardless of how many candidates there are. ---- Election-Methods mailing list - see http://electorama.com/em for list info
