[EM] Why Not Condorcet?

[robert bristow-johnson]

On May 13, 2010, at 10:08 PM, Dave Ketchum wrote:

> I read of arranging ballot data in a triangle, rather than in a  
> matrix as usually described.  A minor detail, but what would be  
> easiest for ballot counters is most important while they count,  
> though rearranging for later processing would be possible.

in all cases, i am assuming that a computer is tabulating the  
ballots.  to count Condorcet by hand is difficult, because (if number  
of candidates is N) you would have to update up to N*(N-1)/2 numbers  
out of N*(N-1) for each ballot handled, rather than 1 of N numbers as  
is done for FPTP (the latter lets you sort to piles for quick double  
checking).

the reason i prefer that triangle (which is just like the NxN matrix  
with half of the elements folded over the main diagonal and also  
sorted in order of the Condorcet ranking (assuming no cycles, if there  
are cycles, even one not including the CW, the triangle won't look so  
pretty) is because it displays the result in such a way that you can  
immediately infer the who-beats-who results from it.  even though i  
haven't seen it anywhere else before, i make no claim to novelty.  i  
really just can't understand why anyone would use the NxN square  
matrix.  it's really hard to glance at it and see what numbers to pair  
together.

--

r b-j                  rbj at audioimagination.com

"Imagination is more important than knowledge."