[EM] Condorcet Criterion for plurality.

[Martin Harper]

LAYTON Craig wrote:

> Martin Harper wrote:
>
> >Hmm - this feels wrong, but it's hard to put into words why... It just
> >seems to me that an integral part of a voting method is the type of
> >ballot - 'plurality-on-preferential' is different to plurality.
>
> What exactly do you mean by 'plurality-on-preferential'?

"Please list all the candidates in your order of preference. We will then
ignore all your lower preferences, and just look at the top candidate on each
ballot paper, counting them up, and making the winner the one with the most
votes". IE plurality defined on preferential ballots - your "single vote
preferential system"

> Nevertheless, it is not a different voting
> method, if you count the ballots the same way.

At the very least, it can change what a 'sincere' vote is - suppose you have a
particularly twisted plurality-like method, which is counted in exactly the
same way - most crosses wins - but where the instructions on the ballot read:
"mark a cross next to the person you'd least like to be elected"

If you vote sincerely, then you vote for the person you'd least like to be
elected. Which is pretty much the worst possible thing to do from a strategic
point of view, of course.