[EM] Strategy in two kinds of FBC/ABE methods

MIKE OSSIPOFF nkklrp at hotmail.com
Tue Jan 24 21:20:23 PST 2012

At first the only FBC/ABE method we knew of was MMPO. Then MDDTR. But both had criticisms which, though I don't recognize their importance, could still be used against them in an enactment campaign. Other than those, there are my conditional methods, and Chris's ICT. ICT avoids the co-operation/defection problem by completing Improved Condorcet with a top-count. But the fact that it uses a pairwise count makes it vulnerable to the offensive strategies of burial and offensive truncation. As I said, that's mitigated by the fact that those strategies can ony help a more favorite candidate. But that strategic consequence of pairwise-count is still there.  As I said, the top-count is what avoids the co-operation/defection problem. But, when AOC uses conditionality-by-top-count, one of thekinds of conditionality that I've suggested, it's making use of the same solution. Let me repeat how that simple kind of conditionalitly works:Give top rating to the candidates you approve unconditonally. Give middle rating to those you approve conditionally. They'll get an approvalfrom you only if they get more top ratings than do your top-rated candidates. I prefer conditionality by mutuality, but what I described in the previous paragraph avoids the kind of calculations needed by mutuality-conditionality, while retaining optionality by candidate. All of the methods that I call "conditional methods" are simply and closely based on Approval, thereby having Approval's avoidance of many strategy  problems that other methods have. And the conditionality gets rid of Approval's remaining problem, the co-operation/defection problem. Ordinary Approval is good enough. We've discussed various ways of dealing with ABE in ordinary Approval. Forest's diplomatic solution. Or publicilzed principled refusal of a compromise. It's been shown that Approval will soon home in on the voter median, avoiding an unliked Myerson-Weber equilibrium. The conditional methods have been objected to by someone, on the grounds that he doesn't like coalition, or doesn't like conditionality. 1. As I said, "... then is it important to you that you not help the people whose help you want?"2. Any method that elects C in the ABE, if B voters don't co-operate, is, itself, conditional, even if not explicitly. The simple, direct, obvious and transparent explicit conditionality of the conditional methods, used with Approval, and Approval-basedmethods such as MTA, MCA and ABucklin, avoids the strategy problems of other methods, without adding one.  Of course all ballots-only nonprobabilistic methods have strategy. The strategy considerations that the conditional methods have are not problems, by that term's meaning in discussions of other methods. I'm only comparing the conditional methods to other ballots-only methods. And, as I've said, the conditional methods have the advantage of being obvious and simple improvements on Approval. So closely related to Approval are they that AOC, MTAOC, MCAOC and AOCBucklin can be offered together as options in an Approval election. Options areuncontrovesial, and difficult to criticize. Mike Ossipoff    		 	   		  
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