Ossipoff: But if Warren has a quibble about what it means to fully vote X
over Y, then
I refer him to my criteria SFC, GSFC, and SDSC.
--WDS: here is the definition of SFC given by Ossipoff (CW=Condorcet
winner):
"SFC: If no one falsifies a preference, and there's a CW, and a majority
of all the voters
prefer the CW to candidate Y, and vote sincerely, then Y shouldn't win."
Ossipoff: "[SFC] is met by SSD and other good wv Condorcet versions."
Ossipoff: "I call [SFC] the pinnacle of the promise of rank-balloting."
However, Ossipoff is wrong. Here is a counterexample. There are 3 voters:
A>B>C
B>C>A
C>A>B *
where the * vote is insincere. The unstarred two voters are a "majority"
who prefer the sincere-CW (who is B) over C, and who vote sincerely. But
the total vote
is a 3-way perfect tie. Therefore C can win. But according to Ossipoff's
SFC, C cannot
win. This counterexample works against every Condorcet method satisfying
anonymity.
I reply now:
Warrens example doesnt show any candidate pairewise-beating each of the
others. He explains that by saying that the asterisk-marked ballot is
insincere. If he means that it falsifies a preference, then his example
doesnt meet the premises of SFD, and so SFC has nothing to say about what
should happen in his example.
Warren quoted SFC above, and so he shouldnt be giving to us an example that
has falsified preferences.
Mike Ossipoff
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