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Technical discussion of election methods

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Beatpath question

JQ
Jameson Quinn
Mon, Oct 5, 2015 3:34 PM

I can show (under reasonable strategic assumptions) that my delegated
system SODA elects one of the candidates who beats all with a winning vote
beatpath of length 2 or less, if there is any such candidate. "A beats B
with a winning vote beatpath of length 2" means: there is some C such that
the minimium of (votes for A against C, votes for C against B) is greater
than votes for B against A.

Obviously, if we allow any length of beatpath, and if there are no ties,
there must be some beats-all winner. But is it possible that there is no
winner with beatpaths of length 2 or less? Can anybody give an example of
such an electorate?

Jameson

I can show (under reasonable strategic assumptions) that my delegated system SODA elects one of the candidates who beats all with a winning vote beatpath of length 2 or less, if there is any such candidate. "A beats B with a winning vote beatpath of length 2" means: there is some C such that the minimium of (votes for A against C, votes for C against B) is greater than votes for B against A. Obviously, if we allow any length of beatpath, and if there are no ties, there must be some beats-all winner. But is it possible that there is no winner with beatpaths of length 2 or less? Can anybody give an example of such an electorate? Jameson