[EM] Problems with finding the probable best governor

[Bart Ingles]

Markus Schulze wrote:

> Also Mike's statement that the Condorcet winner usually has a
> high SUE seems to me to be not justified. Especially in a divided
> society, the SUE of the Condorcet winner and even of the majority
> winner can be very small. The reason why I support the majority
> criterion (resp. the Condorcet criterion) is not that the
> majority winner (resp. the Condorcet winner) usually has a high
> SUE but that a method that meets the majority criterion (resp.
> the Condorcet criterion) is less manipulable.

One thing to note is that the two are not necessarily in conflict, since
the Condorcet criterion is concerned with actual votes cast, and SU is
an aggregation of voters' internal preference levels.  

Of course, to meet both some voters must refrain from listing all
preferences on the ballot.  This suggests either a system that doesn't
allow full ranking, or one with a fairly strong incentive to truncate.

The latter may already exist in at least some pairwise methods -- the
way to test this would be to run simulations of identical elections with
and without truncation, and see whether the truncators improve their own
expected utilities.

Bart