[EM] 3 or more choices - Condorcet

Kristofer Munsterhjelm km_elmet at lavabit.com
Sat Sep 29 13:11:20 PDT 2012


On 09/28/2012 10:11 PM, DNOW1 at aol.com wrote:
> A > B
>
> Choice C comes along.
>
> C may - head to head ---
>
> 1. Beat both
> C > A
> C > B
> 2. Lose to both
> A > C
> B > C
> 3. Beat A ---- BUT lose to B
> C > A > B > C
>
> Thus, obviously, a tiebreaker is needed in case 3.
> Obviously perhaps Approval.
>
> i.e. BOTH number votes and YES/NO Approval votes.
>
> Obviously much more complex with 4 or more choices.
> ---
> ANY election reform method in the U.S.A. has to get past the math
> challeged appointed folks in SCOTUS.
>
> i.e. ANY reform must be REALLY SIMPLE.
> --------
> Condorcet applies for legislative bodies and single or multiple
> executive/judicial offices.

I think Ranked Pairs is the simplest "strong" Condorcet method. You sort 
the pairwise victories so that the strongest comes first, then you go 
down the list, adding that victory to the final order unless it would 
contradict something you added earlier.

So say you have

100 voters prefer A to B
80 voters prefer B to C
85 voters prefer C to A

which would give you:

First the result must place A higher than B. (Okay.)
Second, the result must place C higher than A. (Okay.)
Third, the result must place B higher than C... but that's impossible 
because C is higher than A is higher than B. So skip it.

And the winner is thus C. A comes second, and B third.

-

On the other hand, Schulze is being used more widely, so it's a question 
of what will be more persuasive: saying "this thing is simple", or "this 
thing is used lots of places".




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