Nondeterminism is a delightful way of skirting the Gibbard-Satterthwaite theorem. All parties can be coaxed into exposing their true opinions by resorting or the threat of resorting to chance.
I don't dispute that. The nondeterminsitc methods I have seen appear to be designed to tease out a compromise because a majority cannot throw its weight around. The abilities of nondeterministic methods to generate compromises is formidable, but since we speak of utility, I would like to point something out. 1) Using Bayesian utility, randomness is worse than FPTP. This is a pretty powerful indict, depending on how often the method has to resort to random ballot. 2) False compromises are damaging The reduced power of a majority means that at any choice with a greater-than-random-ballot average utility is a "good compromise" Notice how lousy the Bayesian utility of random ballot is and you begin to see my point. The fallback method produces crappy candidates. People are encouraged to compromise for crappy candidates. Also note that the method for determining the compromise is majoritarian (to the extent that approval is) so the intermediate compromise procedure is a red herring that produces some nasty side-effects. The compromise is determined to be the most-supported at-least-above-average candidate. How does this avoid the original criticism of majoritarian methods? ---- Election-Methods mailing list - see http://electorama.com/em for list info
