[EM] MMV and resolvability

Anders Kaseorg andersk at MIT.EDU
Sat Dec 7 21:51:00 PST 2013


On 12/07/2013 11:01 PM, Michael Ossipoff wrote:
> By the way, do you have a set of ranings that gives the pairwise
> defeats in your example?

One isn’t difficult to construct:

4: B > C > D > A
6: C > A > B > D
4: D > A > B > C
2: D > B > A > C

Defeats:
10/6: A > B, B > C, C > D, D > A, B > D, C > A
MMV result: four-way tie

But now if one voter switches from C > A > B > D to A > C > B > D:

4: B > C > D > A
5: C > A > B > D
1: A > C > B > D
4: D > A > B > C
2: D > B > A > C

Defeats:
10/6: A > B, B > C, C > D, D > A, B > D
9/7: C > A
MMV result: C > A

(On the other hand, it’s not clear what it means for the result to be “C 
 > A” when B and D are still tied with both C and A; in some sense, this 
is still a four-way tie.  The newer example that Markus just posted 
looks like it will be more convincing.)

Anders



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