On Jun 17, 2010, at 8:28 PM, [email protected] wrote:
Chris,
I like this method. It accomplishes more simply what I was trying
to do with some of my DSV approval
methods:
Voters can approve good candidates with less risk for regret,
because if their lower approvals wreck an
approval victory of their favorite, the IBIFA method detects this
state and compensates for it.
Both the three slot and four slot versions seem like definite
improvements over both Approval and Bucklin
without sacrificing the FBC, definitely worth testing and examining
in more depth.
Forest
----- Original Message -----
From: Chris Benham
Date: Wednesday, June 16, 2010 10:27 am
Subject: Irrelevant Ballots Independent Fallback Approval (IBIFA)
To: EM
Cc: Kevin Venzke
... ignoring ratings
It can also be adapted for use with ranked ballots:
*Voters rank the candidates, beginning with those they most
prefer. Equal-ranking and truncation
are allowed.
Ranking above at least one other candidate is interpreted as
Approval.
So, if I bullet vote, my one ranked candidate is disapproved as
Bottom!!!
Leaves me still liking Condorcet, which is less into ranking patterns
(only considers pairs of candidates from a ballot, comparing the
rankings within each pair).
Dave Ketchum
The ballots are interpreted as multi-slot ratings ballots thus:
An approved candidate ranked below zero other candidates is
interpreted as Top-Rated.
An approved candidate ranked below one other candidate is
interpreted as being in the second-highest
ratings slot.
An approved candidate ranked below two other candidates is
interpreted as being in the third-highest
ratings slot (even if this means the second-highest ratings slot
is left empty).
An approved candidate ranked below three other candidates is
interpreted as being in the fourth-highest
ratings slot (even if this means that a higher ratings slot is
left empty).
And so on.
Say we label these ratings slot from the top A B C D etc.
A candidate X's A score is the number of ballots on which it is
A rated.
A candidate X's A+B score is the number of ballots on which it
is rated A or B.
A candidate X's A+B+C score is the number of ballots on which it
is rated A or B or C.
And so on.
If any candidate X has an A score that is greater than any
other candidate's approval score on ballots
that don't A-rate X, then elect the X with the greatest A score.
Otherwise, if any candidate X has an A+B score that is greater
than any other candidate's approval score
on ballots that don't A-rate of B-rate X, then elect the X with
the greatest A+B score.
And so on as in the versions that use a fixed number of ratings
slots, if necessary electing the most
approved candidate.*
This is analogous with ER-Bucklin(whole) on ranked ballots:
http://wiki.electorama.com/wiki/ER-Bucklin
Chris Benham
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