Note that, according to Gibbard and Satterthwaite, all of the systems I am considering here are sometimes vulnerable to voter manipulation. Satisfying the criteria I find important tends to minimize chances for manipulation.
Baldwin | Borda | Bucklin | Carey | Coombs | Copeland | Dodgson | Hare | Nanson | Raynaud | Schulze | Simpson | Tideman | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pareto-optimal? | YES | YES | YES | YES | YES | YES | YES | YES | YES | YES | YES | YES | YES |
majority? | YES | NO | YES | YES | NO | YES | YES | YES | YES | YES | YES | YES | YES |
Condorcet? | YES | NO | NO | NO | NO | YES | YES | NO | YES | YES | YES | YES | YES |
monotonic? | NO | YES | YES | NO | NO | YES | YES | NO | NO | NO | YES | YES | YES |
clone-independent? | NO | NO | NO | NO | NO | NO | NO | YES | NO | YES | YES | NO | YES |
mutual majority? | YES | NO | YES | NO | NO | YES | NO | YES | YES | YES | YES | NO | YES |
Smith? | YES | NO | NO | NO | NO | YES | NO | NO | YES | YES | YES | NO | YES |
reverse-symmetric? | NO | YES | NO | NO | NO | YES | NO | NO | NO | NO | YES | NO | YES |
reinforcing? | NO | YES | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO |
Schwartz? | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO | YES | NO | NO |
nonmanipulable? | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO | NO |
# Coombs fails reinforcement |
# precinct 1 |
8:B>C>A>D |
6:C>D>A>B |
4:D>B>C>A |
# precinct 2 |
8:B>A>D>C |
2:B>C>D>A |
6:C>A>D>B |
2:C>B>D>A |
2:D>B>C>A |
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