[EM] This might be the method we've been looking for:
fsimmons at pcc.edu
fsimmons at pcc.edu
Fri Dec 2 16:32:44 PST 2011
This new method (Top Tier Pairwise Rule modified MinMax) gives a satisfactory resolution to "Kevin's
Bad MMPO Example:"
49 A
01 A=C
01 B=C
49 B
It yields a tie between A and B.
Shall we call the method MinMax(TTPR)?
----- Original Message -----
From:
Date: Friday, December 2, 2011 4:12 pm
Subject: This might be the method we've been looking for:
To: election-methods at lists.electorama.com,
> Here’s a method that seems to have the important properties that
> we have been worrying about lately:
>
> (1) For each ballot beta, construct two matrices M1 and M2:
> In row X and column Y of matrix M1, enter a one if ballot beta
> rates X above Y or if beta gives a top
> rating to X. Otherwise enter a zero.
> IN row X and column y of matrix M2, enter a 1 if y is rated
> strictly above x on beta. Otherwise enter a
> zero.
>
> (2) Sum the matrices M1 and M2 over all ballots beta.
>
> (3) Let M be the difference of these respective sums
> .
> (4) Elect the candidate who has the (algebraically) greatest
> minimum row value in matrix M.
>
> Consider the scenario
> 49 C
> 27 A>B
> 24 B>A
> Since there are no equal top ratings, the method elects the same
> candidate A as minmax margins
> would.
>
> In the case
> 49 C
> 27 A>B
> 24 B
> There are no equal top ratings, so the method gives the same
> result as minmax margins, namely C wins
> (by the tie breaking rule based on second lowest row value
> between B and C).
>
> Now for
> 49 C
> 27 A=B
> 24 B
> In this case B wins, so the A supporters have a way of stopping
> C from being elected when they know
> that the B voters really are indifferent between A and C.
>
> The equal top rule for matrix M1 essentially transforms minmax
> into a method satisfying the FBC.
>
> Thoughts?
>
More information about the Election-Methods
mailing list