[EM] My Favorite Deterministic Condorcet Efficient Method: TACC

[C.Benham]

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