[EM] "scored condorcet", etc

Gervase Lam gervase.lam at group.force9.co.uk
Wed Nov 23 15:21:11 PST 2005


> Date: Wed, 23 Nov 2005 00:30:35 +0000 (UTC)
> From: Rob Brown
> Subject: Re: [EM] "scored condorcet", etc

> > Candidate's Score = Total No. of Ballots - Max wv against Candidate
> 
> That's close to what I was thinking.  I probably would, rather than
> using "total
> number of ballots", use something that can be derived from the
> pairwise matrix,
> which the total number of ballots isn't.

In a similar vein to Forest's O/D (Offense/Defense) method, which is a
variation of MMPO, you could do the following:

Candidate's Score = Min votes FOR Candidate - Max votes AGAINST
Candidate

The Candidate with the highest score is the winner.  This is the same as
MMPO except that "Min votes for Candidate" has been included in the
formula.  The problem with adding the "Min votes FOR Candidate" is that
I think it makes the method not satisfy FBC.

In Forest's O/D method, the minus is turned into a divide and for each
pair of candidates, if both candidates are ranked equal first (or last),
they are counted as votes for (or against) the candidate in the pairwise
matrix.  I think O/D (with the said first/last rankings handling)
satisfies FBC.

> It would be nice if the score could be represented in a way that
> compares to
> percentage, so that all scores add up to 100.

This just requires a bit school pupil mathematics to do this.

Thanks,
Gervase.





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