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

[Juho Laatu]

On 7.6.2011, at 10.53, Peter Zbornik wrote:

> I'd say that FBC (and LNH) is quite a big problem for Condorcet
> methods, at least for someone (like me) who think sincere voting
> should be the norm.

One could also claim that in typical political elections Condorcet methods will work fine, and people need not worry about the fact that these methods fail FBC and LNH. FBC does not mean that there would be a clear need to consider "betraying" one's favourite candidate, and LNH does not mean that there would be a clear need to consider truncating one's vote in order not to harm oneself. A much better advice to the voters is to vote sincerely. (And I note again that I have not seen good general advices on how people could in practice exploit the theoretical vulnerabilities of Condorcet methods in real elections.)

> It seems that there is a risk, that Condorcet methods are reduced to
> plurality-like methods due to voting strategies that exploit the fact
> that FBC and LNH do not hold.

That could happen in principle, but I believe in most environments that would not be the case. And even if that would happen, probably those fears (leading to bullet voting or plurality-like methods) would be irrational.

Juho