Hi Mike,
--- En date de : Mar 1.11.11, MIKE OSSIPOFF <nkk...@hotmail.com> a écrit :
A criterion compliance chart:
-----------------FBC--------3P-----3PD--------UP----ABE
Bucklin---------Yes--------Yes-----Yes--------Yes----No
MDDA----------Yes---------Yes----Yes---------No----No
DP--------------Yes---------Yes-----No---------No----Yes
MCA------------Yes---------Yes-----No---------No----No
MAMPO---------Yes---------No-----No----------No---No
IRV(= whole)---Yes-------Yes-----Yes--------Yes---Yes
ER-IRV(whole) doesn't satisfy FBC. You may need to demote your favorite in order
to get a preferable elimination order.
Also, I do plan at some point to find an FBC failure of MMPO//MMPO//MMPO//etc.
I'm thinking it may require four candidates. My idea is that by lowering your
favorite,
you knock your favorite out of a tie, so that only two candidates remain. But
if there
were a three-way tie with no other candidates, MMPO would be stuck. So there
must be a fourth candidate available to be eliminated and allow the method to
proceed.
Maybe I can reword slightly what Jameson said:
If sincere scenario (plus specific assumptions of voter sincerity) "S" can give
rise to
cast ballots B, and a criterion C says S must have outcome O, then any method
is
going to have to select outcome O whenever the cast ballots are B. The
criterion in
effect is requiring this, even when the scenario isn't S.
It's like how SFC is supposed to protect sincere CWs, but in practice it ends
up
also defending some candidates who just look like they *might* be sincere CWs.
Kevin
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