Regarding my example
31: A>B
32: B>C
37: C>A
Forest:
>
> >I've come around to the belief that most Condorcet cycles in
> ordinary elections
> >are artificial, so chances are that this cycle was created from
> the burial of B
> >by the C faction. Giving C the win only rewards this manipulation.
>
>
> Chris:
> I can't see any remotely rational justification for assuming
> that this is the case
> rather than, say, the cycle was created by the A voters burying C.
Forest:
Well, usually the largest faction is the one with the best chance of
getting away with it, and would get
away with it under Beatpath, Ranked pairs, etc. unless the Condorcet
supporters took defensive action.
With TACC no defensive action was necessary.
Now let's consider the possibility that you suggest, namely that the
true preferences were
31 A>C
32 B>C
37 C>A
If there is enough information for the A faction to think it is safe
to bury C, then there is enough
information for the C faction to take the precaution of truncating A
defensively.
The we have
31 A>B
32 B>C
37 C
That's why I think this scenario is less likely than the one I suggested.
Chris:
Yes, but only somewhat. This all assumes that the A faction's pairwise
preferences are all about equally
strong, that accurate pre-poll data is available to all the factions,
and that the C faction voters are strategically
minded.
It is nothing like a sufficient counter to my original central point,
that on the ballots as voted C is the strongest
candidate and solidly dominates the TACC winner A.
Interpreting the ballots as 3-slot ratings, C has the highest Approval
score and the the highest Top-Ratings
score. And C pairwise beats A
Let me modify my example to further strengthen C and weaken A:
25: A>B ("sincere" is A)
06: A>C
32: B>C
27: C>A
10: C
Approvals: B57, A58, C75. ("Top-Ratings" as before).
A>B 58-32, B>C 57-43, C>A 69-31.
TACC still elects A.
C is the "sincere CW". C's voted pairwise defeat is the weakest (as
measured by both Winning Votes and
Margins) while A's is (by those same measures) is the strongest.
Chris Benham
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