Id like to improve my three examples that I posted the other day, so that
theyre genuine FBC failure examples for DMC.
In these examples, with DMC, either the B &/or C voters need to use informed
Approval strategy to save the CW, enforce majority rule, and defeat the
greater evil, or else one C voter could achieve that by burying his
favorite.
52: AC (offensive order-reversal)
100: BA
50: C/B
103: A
100: B
102: C/B
3: A
100: BA
102: C/B
In the second two examples, the truncation examples, as before, DMC requires
the use of informed Approval strategy to save the CW, enforce majority rule,
and defeat the greater evil, while MDDA, MAMPO, and wv Condorcet dont
require any strategy at all.
Well, the exception now is that, in DMC, in all three examples, one C voter
can accomplish those goals by voting B>C, burying his favorite. With these
improved examples, theres no other way he can achieve that.
Again, in the truncation examples, no one has to do anything to achieve
those goals in MDDA, MAMPO and wv Condorcet.
To say what MDDA and MAMPO would do, using these ballots, Im speaking of
versions of those methods that use an Approval cutoff instead of saying that
all ranked candidates are approved. Thats for the purpose of comparability
with DMC using that balloting.
In the first example, with wv Condorcet, no one has to use any strategy to
achieve those goals.
With MDDA, that one C voter could achieve it by merely voting B = C, in that
example. With MAMPO, he couldnt achieve it--but, as always with MAMPO &
MDDA, theres no incentive to favorite-bury. If approval by half the voters
were enough to avoid disqualification, then that C voter could save the CW
by ranking B = C. But the rules say that B is disqualified unless a majority
approve him, and so that one C voter cant save B in that example in MAMPO.
Of course thats good, because it wont give him incentive to favorite-bury.
Mike Ossipoff
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