> 8) Others may disagree, but I think it has just the right amount of > runoffs. Essentially (provably???), there would only be runoffs if there's > no known honest CW; in which case, further deliberation by the voters is > completely appropriate. >
Again I looked more deeply at an unproven claim I'd made; and again, RMCA came out even better than I thought. Somebody pinch me; I had given up on finding such a "perfect" system. So, let's recap. In the first email, I claimed that "correct" strategy if there's a known CW is to rank them alone (except for no-hopes) at their ranking level. If there are candidates both above and below them, that would put them in the middle rank. This is not sufficient to guarantee one-round decisiveness. Say that more people rank X>>CW than CW>>X + ((CW>X) / 2); then X would be RW and it would go to a runoff. In order for that to happen, there would have to be a number of weak CW>X ballots. There are two kinds: CW>X>.... or ....>CW>X. If ballots of the first kind (prefer CW and approve X) are necessary to make X a RW, those voters - whose favorite is the CW - could easily bullet vote. By not bullet-voting, they are saying "I am willing to consider these two candidates again, in a runoff; because I know that if nobody changes their mind, my candidate will win that runoff". It is entirely up to them; they are essentially making an explicit, nonstrategic choice that a runoff could be healthy. The second kind of ballots are not quite so clear-cut. By voting ...>CW>X instead of CW,...>>X, these voters are simply refusing to semi-betray their favorite(s). However, that does say something about the strength of their CW>X preferences, and it seems entirely reasonable to go to a runoff. If the X>>CW voters really do care significantly more, they will turn out in higher numbers and win; if not, and if nobody changes their mind, the CW will win. So voter strategy if there's a known CW is: 1) Understand that a runoff will not change the ultimate result, unless people change their minds or turnout patterns change significantly. 2) If, given that, you don't mind a runoff, vote the CW in a rank by themselves. If the CW is your current favorite, approve only candidates you'd like to have a second look at in a runoff. 3) If your preference for avoiding a runoff is stronger than your preference against ranking the CW equal to your favorite, and the CW is not your least favorite, then top-rank (prefer) the CW and approve nobody. 4) If the CW is your least favorite, then top-rank (prefer) the candidate who you think would have the best chance of changing peoples minds (becoming the honest CW) in a runoff, as well as everyone you like better; approve all other candidates; and disapprove the CW. That's pretty easy and intuitive. If people vote like this, unwanted runoffs would be very rare. JQ
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