[EM] Condorcet Violates Strong FBC

[Alex Small]

Elisabeth Varin/Stephane Rouillon said:
> Alex,
> does any method satisfy strong FBC?

Good question.  I know that Condorcet methods don't, and monotonic
majoritarian methods don't.  Rated methods don't.  If I could show that
majoritarian methods don't, irrespective of montonicity, I'd be
satisfied.  We know that IRV is non-monotonic but majoritarian, but it
doesn't satisfy strong FBC.  Maybe I need different techniques.

I started looking at the case where we remove monotonicity.  You have to
consider the possibility that favorite betrayal gives the same result as
a voter changing his preference from A>B>C to A>C>B.  Then you have a
new electorate.  But then you have to look at the new electorate and try
to figure out which faction to tinker with.  The number of scenarios to
consider grows out of control.  If I can just find a path out of that,
one that takes me in a circle to expose a contradiction, I'll be happy.

Any thoughts on extending the current results to 4 or more candidates?



Alex



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