[EM] Challenge2 - give an example where MFBC is violated for Condorcet methods

[Kevin Venzke]

Hi Peter,

This is how I look for (and usually define) FBC failures: Lowering a
candidate from the top position should not move the win from somebody
not ranked top to somebody who was ranked top. (It could be the lowered
candidate, but that's a bigger concern.)

I don't know about your method, but with the standard symmetrically-
completed Schulze etc. you have the theoretical conflict that symmetric-
completion wants to make it less useful to use equal ranking ("tell a
half-truth") while what FBC is saying you won't have to do any worse than
tell a half-truth, regarding your true favorite. So if SC succeeds in
dissuading people from casting equal rankings, the only way it could
satisfy FBC is by offering an even better guarantee.

I don't know about your modified criteria, either, but standard weak FBC
is very hard to satisfy.

Kevin Venzke