From James Green-Armytage's paper on election strategy:
I focus on the nine single-winner voting rules that I consider to be
the most widely known, the most widely advocated, and the most broadly
representative of single-winner rules in general:
these are plurality, runoff, alternative vote, minimax, Borda,
Bucklin, Coombs, range voting, and approval voting8.
I would think that Schulze(Winning Votes) is more "widely advocated"
than "minimax", aka MinMax(Margins).
2. Preliminary definitions
2.1. Voting rule definitions
In this paper, I analyze nine single-winner voting methods. I follow
Chamberlin (1985) in including plurality, Hare (or the alternative
vote), Coombs, and Borda, and to these I add two round runoff, minimax
(a Condorcet method), Bucklin, approval voting, and range voting. My
assumption about incomplete ranked ballots is that candidates not
explicitly ranked are treated as being tied for last place, below all
ranked candidates. My assumption about votes that give equal rankings
to two or more candidates is that they are cast as the average of all
possible orders allowed by the rankings that they do specify.
http://www.econ.ucsb.edu/~armytage/svn2010.pdf
I find these "assumptions" about ballots that are truncated or have
equal-ranking to be very unsatisfactory.
It means that the version of Bucklin you are considering is a strange
one (advocated by no-one) that fails the
Favorite Betrayal criterion. It would also fail Later-no-Help, which is
met by normal Bucklin.
It means that the only version of minimax you can consider is Margins,
and you can't consider Schulze(Winning Votes).
Unlike minimax(margins), Schulze(WV) meets the Plurality, Smith and
Minimal Defense criteria.
Alternative vote, or Hare: Each voter ranks the candidates in order of
preference. The candidate with the fewest first choice votes (ballots
ranking them above all other candidates in the race) is eliminated.
The process repeats until one candidate remains.
Coombs12: This method is the same as Hare, except that instead of
eliminating the candidate with the fewest first-choice votes in each
round, it eliminates the candidate with the most last-choice votes in
each round.
Surely this is a museum curiosity that no-one currently advocates? This
fails Majority Favourite, but I think there
is another version with a 'majority stopping rule'.
http://wiki.electorama.com/wiki/Coombs%27_method
http://en.wikipedia.org/wiki/Coombs'_method
http://www.fact-index.com/c/co/coombs__method.html
6.2.2. Compromising strategy results
Tables 9-11 and figures 10-12 show the voting rules‘ vulnerability to
the compromising strategy, given various specifications. As shown in
proposition 4, Coombs is immune to the compromising strategy
Of course the version with the majority stopping rule isn't immune to
that strategy (Compromise).
Chris Benham
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