ied-at-Top-Pairwise-Beats-All, Top Ratings.
In keeping with Kevin's naming, and reflecting its relation to ICA, it could be
called
Improved Condorcet-Top (ICT).
I'll use that because it's shorter.
One thing that I like about the tied-at-top methods is that they elect A in the
ABE,
meaning that one-sided coalition support is sufficient to defeat C, but without
giving
the election away to B.
Of course the election of A violates the Plurality Criterion, but that's fine
with me.
To me, the _practical_ advantage described in the previous paragraph is worth
more than
the non-practical, aesthetic, Plurality Criterion.
ICT has burial strategy. In the ABE, the B voters can make B win by burying A,
by middle-
rating C but not A. Then A doesn't have any indifference on his side, in hir
comparison
with C.
But B still beats C, because B>C is still greater than C>B. For the same
reason, C
still doesn't beat everyone.
And B still beats A, because
B>A + B=A is greater than A>B.
So B is now the only beats-all candidate. B wins.
As currently defined, ICT elects C in Kevin's MMPO bad-example.
No one is indifferent between A and B.
So, since A=B is zero, then A>B + A=B is no greater than B>A.
Likewise vice-versa, of course, since A & B are symmetrically-related.
Therefore, neither beats the other.
Maybe that can be fixed, by defining "beat" in the opposite way, so that x
beats y
if x>y is greater than y>x + x=y, and then saying that the winning set is the
set
of unbeaten candidates.
In summary, ICT does three things that some find unacceptable:
1. Plurality Criterion violation
2. Successful burial strategy
3. Noncompliance in Kevin's MMPO bad-example.
#1 and #2 aren't a problem to me. #2 could be, but I don't know what
burial-deterrence
ICT has.
With the sole exception of MMT, the conditional methods meet Mono-Add-Plump.
They probably meet the Plurality Criterion too, because of their close relation
to
Approval. If B defects, those methods elect C, in compliance with the Plurality
Criterion.
Burial strategy has no meaning in the conditional methods. As I've been saying,
they're
a completely new kind of method, with a new kind of strategy, a milder strategy.
Mike Ossipoff
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