[EM] simpler proof of "no conflict theorem" now trivial

[Paul Kislanko]

Sentences should have subjects and predicates.

-----Original Message-----
From: election-methods-bounces at electorama.com
[mailto:election-methods-bounces at electorama.com] On Behalf Of Dave Ketchum
Sent: Sunday, August 20, 2006 9:08 PM
To: Jonathan Lundell
Cc: election-methods at electorama.com
Subject: Re: [EM] simpler proof of "no conflict theorem" now trivial

Maybe time to start over, unless someone can find something decent written 
down!

We are talking of ranked choice, such as IRV does.

Normally possible to rank every candidate.  Restrictions tolerable, but 
MUST be able to rank at least best and second.

Equal ranks permitted, when the voter sees a tie in value.

Cycles must be expected and attended to.  Here there are various ways of 
attending to choose from.

BTW - I choke on the word "sincere" - I keep my work tolerable by 
accepting a ballot as being what the voter meant!  Anyway, rare for a 
voter to know enough about what other voters - guessing what this voter 
might do - do in response.

DWK

On Sun, 20 Aug 2006 13:35:14 -0700 Jonathan Lundell wrote:
> At 4:58 PM -0700 8/16/06, David Cary wrote:
> 
>>Without knowing the exact wording of the criterion, it can be very
>>difficult to judge whether or not an election method meets the
>>criterion, or whether the criterion makes sense or contains
>>ambiguities. 
>>
>>As stated on Wikipedia (
>>http://en.wikipedia.org/wiki/Condorcet_criterion ), there is
>>certainly some ambiguity, as mentioned on the discussion page:
>>
>>"The Condorcet criterion for a voting system is that it chooses the
>>Condorcet winner when one exists."
>>
>>"The Condorcet candidate or Condorcet winner of an election is the
>>candidate who, when compared in turn with each of the other
>>candidates, is preferred over the other candidate."
>>
>>The ambiguity is about exactly how candidates are compared with each
>>other and what preferences are to be used.  The balloted preferences
>>of the voting system in question? The sincere preferences of the
>>voters? Is there a hidden presumption that voters cast ballots that
>>are sincere, or are at least consistent with their sincere
>>preferences?  Is the Condorcet criterion only applicable to certain
>>kinds of election methods?
> 
> 
> Good point. The previously cited paper "In Praise of Manipulation" is 
> problematical in this regard, in that the authors get way too literal 
> about the meaning of "sincere".
> 
> I take the meaning of "preferred" above to equivalent to asking the 
> voter in question to break a tie between the two candidates. If your 
> vote will swing the outcome, which of these two candidates would you 
> choose for the seat to be filled?
> 
> The problem is, of course, that this is seldom if ever the context in 
> which the voter actually marks a ballot, often for strategic reasons 
> (fear of wasting a vote, wanting to bury a close competitor, etc).
> 
> Hence the desirability of an election method that encourages a 
> rational voter to cast a sincere ballot.
> 
> 
>>The more these ambiguities are resolved to make the Condorcet winner
>>dependent on the election method under consideration, the easier it
>>may be for an election method to satisfy the Condorcet criterion.
>>
>>The Wikipedia article is notably lacking any references.
> 
> 
> Many of the election-methods Wikipedia articles leave a lot to be 
> desired (the Droop quota article is a good (bad) example).
-- 
  davek at clarityconnect.com    people.clarityconnect.com/webpages3/davek
  Dave Ketchum   108 Halstead Ave, Owego, NY  13827-1708   607-687-5026
            Do to no one what you would not want done to you.
                  If you want peace, work for justice.


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