[EM] TTPBA//TR (a 3-slot ABE solution)

[C.Benham]

I have conferred off-list with Kevin Venzke, and now agree with him that 
the "Tied at Top Pairwise Disqualification, Top Ratings" method  I 
suggested (20 Nov 2011) almost certainly does fail the FBC, so
I withdraw that proposal and instead suggest this simpler method:

*Voters submit 3-slot ratings ballots, default rating is Bottom 
signifying least preferred, Top rating signifies most preferred, the 
other ratings slot is Middle.

According to the "Tied-at-the-Top" pairwise rule (TTP), candidate X 
beats candidate Y if the number of ballots on which X is given a higher 
rating than Y *plus the number of ballots on which X and Y are both 
rated Top*  is greater than the number of ballots on which Y is given a 
higher rating than X.

If  any candidates  (or candidate)  TTP beats all other candidates, 
elect the one of these with the highest Top-Ratings (TR) score.

Otherwise elect the candidate with the highest TR score.*


I call this "Tied at Top rule Pairwise Beats-All// Top Ratings" 
(TTPBA//TR). 

It is similar to Kevin Venke's  Improved Condorcet//Approval (ICA) 
method, the only difference being that it uses Top-Ratings instead of 
Approval.  It was Kevin who invented the special "tied at the top"
pairwise rule.

http://wiki.electorama.com/wiki/index.php?title=Tied_at_the_top

http://wiki.electorama.com/wiki/Improved_Condorcet_Approval

http://nodesiege.tripod.com/elections/#methica

TTPBA//TR  (or TTBA,TR) meets the Plurality and  Mono-add-Plump criteria.

Chris Benham