[EM] suggested improvement on Mutual Majority criterion/set (and MTA reviewd)

2012-01-13 Thread C.Benham

On 21 Dec 2011 I proposed this criterion:


*The winner must come from the smallest set S of candidates about which
the following is true: the number of ballots on which all the members
(or sole member) is voted strictly above all the non-member candidates
is greater than the number of ballots on which a (any)   non-member
candidate is voted strictly above all the members of S.*



That is fairly clear, but the wording could perhaps be improved, say:

*If the number of ballots on which some set S of candidates is  voted 
strictly above all the candidates outside S is greater than the number 
of ballots on which all the members of  S are voted below equal-top
(i.e. strictly below some/any outside-S candidate), then the winner must 
come from S.*


I tentatively suggested the name "Add-Top Proofed Solid Coalition 
Majority".   A bit less clumsy would be "Add-Top Proofed Mutual 
Majority". Maybe there is a better name that either does without the 
word "Majority" or includes another word that qualifies it.  For the 
time being I'll stick with Add-Top Proofed Mutual Majority (ATPMM)




I gave this example:

45: A>B
20: A=B
32: B
03: D

My criterion says that the winner must be A, but Mike Ossipoff's MTA 
method elects B.


I did endorse MTA as an improvement on MCA, but since it (and not MCA) 
fails this (what I consider to be very important) criterion (and is also 
a bit more complicated than MCA) I now withdraw
that endorsement.  I still acknowledge that MTA may be a bit more 
"strategically comfortable" for voters, but I can't give that factor 
enough weight to make MTA acceptable or win its comparison with MCA.


Chris Benham



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

2012-01-13 Thread 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






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[EM] MTA

2012-01-13 Thread MIKE OSSIPOFF

I said that there's no justification to propose or use a method any more 
complicated than Approval, unless
it avoids the co-operation/defection problem.

MTA and MCA both elect B in the Approval bad-example.

It seems to me that, due to some advantage, I decided that I'd vote by MCAOC 
voting instead of MTAOC voting in an Approval
election among the 7 parties that I nominated. But, because I'd like to use 
more than 3 rank-positions, provided that
AERLO is available, I'd use AOCBucklin instead of either in that election.

Without AERLO, strategy becomes much less reliable and knowable with more than 
3 slots.

As I said, I'm not sure whether or not AERLO spoils FBC-compliance, but I 
nevertheless suggest having
it as an option in the poll, and I will use it, if the poll happens. 

But, if AERLO spoils FBC-compliance, I wouldn't propose it publicly.

Mike Ossipoff
  
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