[EM] Blake's margins arguments

Adam Tarr atarr at purdue.edu
Tue Feb 18 05:22:50 PST 2003

Tom McIntyre Wrote:

>>101: A
>>50: BAC
>>100: CBA
>>About 60% of the voters have indicated that they'd rather elect
>>B than A. And so margins elects A.
>>WV counts, keeps, & honors the B>A majority. A has a majority defeat that 
>>wv doesn't lose or erase. With margins, what happens to that majority 
>>against A? Margins erases it.
>And about 60% prefer A to C.  What about honoring *that* majority?  One of 
>these majorities has to be lost.  Both WV and margins count, keep, & honor 
>one of them, and erase the other.

The A over C defeat is not erased.  The only way you could consider that 
defeat erased, would be if C had won the election.  Take the extreme 
example: say there was a fourth candidate, "Adam Tarr", who received zero 
votes.  Does electing A, B, or C constitute "erasing a majority", because 
the other two candidates' defeats of mr. Tarr are not counted?  Of course 
not.  Such a standard would force us to declare every nontrivial 
multicandidate election as a tie.

A defeat can only be considered erased if the candidate who suffered that 
defeat is actually elected.  The only defeat that winning votes overturns 
in the above example is the 100>50 defeat of B by C.  Margins keeps this 
defeat, but overturns the 150>101 defeat of A by B.

I may write a more lengthy follow up to Mike's post, but I won't have time 
until Thursday at the earliest.


For more information about this list (subscribe, unsubscribe, FAQ, etc), 
please see http://www.eskimo.com/~robla/em

More information about the Election-Methods mailing list