[EM] typo

[James Green-Armytage]

James replying to Mike...

>So no, the problem that could result from offensive order-reversal in wv
>is 
>not a new problem, but is only the old problem, much reduced.

	Going from non-burying vulnerable methods (like plurality, runoffs or
IRV) to burying-vulnerable methods (like Condorcet, Borda, Bucklin), the
burying strategy is a new problem in the following sense: In some
scenarios, IRV will pick the Condorcet winner, and strategic incursion
will not be possible... whereas strategic incursion (resulting in the
election of someone other than the sincere CW) will be possible in
Condorcet-efficient methods (e.g. WV).
	In IRV, given sincere preferences A>B>C>D>E..., one cannot increase the
chances of A winning by manipulating preferences after A, one cannot
increase the chances of B winning by manipulating preferences after B, and
so on. In some situations, this prevents strategic possibilities from
opening up. 
	In IRV, if candidate X is the sincere Condorcet winner, and more than 1/3
of the voters rank X in first place, then I think that no strategic
manipulation will be possible, in that no set of voters can gain mutual
advantage by changing the winner to someone else. (You can probably
generalize this from one candidate to a set of candidates, which I earlier
defined as a "dominant mutual third" set.) I don't think that many
pairwise methods share this property. So that would be a new problem,
right? A sincere Condorcet winner with more than 1/3 of the first choice
vote would no longer be totally safe from strategic manipulation.
	Look, I'm not saying that IRV is better than Condorcet. I never have. All
I'm saying is that when you switch from IRV to Condorcet, there is at
least _some_ kind of trade-off. You gain a lot of good, important things,
but at the same time you open the door for new problems, new liabilities.
The point isn't just that Condorcet doesn't always elect the Condorcet
winner in strategic situations (obviously IRV doesn't either, you don't
need to tell me that), but that vulnerability in Condorcet occurs in some
situations where IRV is invulnerable.
	On the whole, the IRV-->Condorcet tradeoff is a good one, but you need to
admit that there is at least some tradeoff.

Sincerely,
James