Condorcet Truncation Counterexample

[MIKE OSSIPOFF]

Steph wrote:

2: A >B >C
4: A >C >B
2: B >A >C
3: B >C >A
2: C >A >B
0: C >B >A

[...]

A (4) > B (2).

Note that A is the Condorcet Winner.

The B >A >C voters (2) decide to believe Bart Ingles and truncate their
ballots to produce insincere votes, namely B ballots.
With winning votes the pairwise comparisons become:

[...]

A(4) > B(2).
Bart wins...
Note that margins and relative margins would preserve Adam's victory.

Do you surrender?

Please tell me where I am wrong or explain,
Steph.

I reply:

Steph, you miscounted the ballots: There are 8 people ranking
A over B.

However, if, as is possible with truncation, a sub-majority number
of people rank A over B, then truncation can steal the election for
that poorly-supported CW. What I claim about wv is that wv methods
meet GSFC & SDSC.

PC(wv) might not meet GSFC, & SDSC, but it at least meets SFC.
& WDSC.

And I claim that margins and relative margins methods fail GSFC
SFC, SDSC, & WDSC.

Actually, I don't just claim those things. I've demonstrated all
of them on EM.

Mike Ossipoff

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