[EM] 3-slot method

Jobst Heitzig heitzig-j at web.de
Mon Nov 15 12:34:19 PST 2004

Dear Chris!

I though some time about your proposal and have some comments:

First of all, it it not Condorcet, is it? It seems to me that in the
following example, it will elect A though C is the CW:
2 A>C>B
4 A>B>C
4 C>B>A
1 C>A>B
2 B>C>A
Defeats A>B(7:6), C>A(7:6), C>B(7:6), hence C is the CW. No candidate is
disapproved by a majority (A:6, B:3, C:4). A is most preferred (6), B is
least disapproved (3), hence A wins!

Did you check any other criteria? I always try Condorcet and
monotonicity first. I fear the latter is quite improbable because of the
 detail "If not all the candidates are rated as Disapproved by a
majority..." and because of the IRV-like promotion in step (3).

I find the idea of reducing to two candidates which are optimal in
different senses somewhat attractive. It reminds me of a suggestion of
Forest who proposed to reduce to three candidates first and then drop
the weakest defeat in case of a cycle.

Yours, Jobst

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