Hi Jameson, A quick reply to your most recent post.
To me, the term "burial" implies burying under something. So, I'd propose: If w is winner when votes are sincere, and voters who prefer q to w change their ballots only by giving w an inferior ranking, or by improving the rating of x, then the winner cannot change fro w to q.
First of all, if you'd like to define a new criterion, I urge you to give it a different name from existing criteria. I'm not just proposing these definitions of burying and compromising now; I've been using them for years -- see for example my 2004 Voting Matters paper. (I originally got the terms from Blake Cretney's condorcet.org web site, though this doesn't seem to be online anymore.) Having more than one criterion with the same name does happen, but when it does, it causes confusion, and signifies poor communication within the intellectual community. Take, for example, the endless muddle over the "independence of irrelevant alternatives" criterion. Another example I've recently discovered is 'local IIA', which has been defined one way on Wikipedia for years, but which had apparently been defined in a different way in the academic literature for several years before that.
Secondly, I find your statement of this new criterion somewhat confusing. Do you mean "*or* by improving..." or "*and* by improving..."? What are the restrictions on the identity of x? Can x be q? Can x be preferred to q?
Why is this better than the first definition, why bring x into it? There is nothing a priori wrong with reducing w's rating leading to w not winning. The problem is when you start using third parties to game the system - because of the inherent risk of misfired strategy leading to unqualified x winning.
To say that this is 'better' than the first definition seems like much too strong a statement. If anything, it's just a different criterion. If my preferences are A>B>C, I estimate that the sincere winner is B, and so I vote A>C>B in the hope of getting A elected, then this is unambiguously a form of insincerity, and yes, it risks getting C elected in some cases. Whether this is 'a priori wrong' seems like a question that is more abstract than necessary.
my best, James ---- Election-Methods mailing list - see http://electorama.com/em for list info
