[EM] Condorcet counting

Dave Ketchum davek at clarityconnect.com
Sat Jan 30 16:30:57 PST 2010

This gets called difficult.

Seemed simpler after I tried staring it down, so I hope my thoughts  
can help.

The diagonal in the N*N matrix (A,A thru Z,Z) should be 0 - so make  
this happen as last step, without worrying before.

Let there be a column n for value for candidates for which there are  
no votes, to be used at the end:
      This could simply be copied in to columns for which there are no  
      It can be added in to other columns if we prepare their values  
to be consistent with this - using add for those selected for copy  
above works since add would have the same effect as copy for them.

Summing matrices, such as from two different precincts:  Align, if  
necessary, such that data for candidate A be added together.  If a  
candidate needs adding, such as for a write-in, initial values for  
that column and row are 0.  Cols n values are simply added.

First ranking on a ballot is for candidate A.  Simply add '1' to  n,A  
- will show A as A>? for that entire row.  Do this for each and every  
candidate ranked by this voter.  Note two ballot formats:
      There being only one place for ranking A, multiple rankings are  
      If ranking can be indicated in multiple ballot fields for A,  
this must be checked for and attended to.

Second ranking is for B.  Must attend to A,B and B,A, for which what  
is said above would be correct if each outranked the other:
      If A=B, neither outranks, so correct by subtracting '1' from each.
      If A>B, subtract '1' from B,A - likewise from A,B for B>A.

Third ranking is for C - treat pairs A-C and B-C like A-B.  Continue  
this pattern if more candidates ranked.

Dave Ketchum

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