Aaron's words make sense, but perhaps I can do better talking about
two methods that, while using the same ballots but going at the task
in different ways, usually agree as to winner.
IRV looks only at best liked, discards candidate with fewest such
votes, and repeats until a winner remains.
Condorcet looks at ALL the ballot rankings, discards candidate liked
less when compared with each other candidate, and repeats until no
such candidates remain.
Since IRV only looks at momentarily best liked, it can discard
candidates Condorcet would see many voters truly liking better.
Condorcet can complete this part with three or more candidates
remaining because they are in near ties such as A>B and B>C and C>A.
This is called a cycle and requires special analysis to decide which
member should win.
Note that cycles require a mixture of voters with differing
goals - no one voter can vote all the inequalities described above.
DWK
On Mon, 28 Jul 2008 17:10:49 -0700 (PDT) Aaron Armitage wrote:
--- On Mon, 7/28/08, James Gilmour <[EMAIL PROTECTED]> wrote:
That all ranked ballot voting systems must be assessed
using criteria and tests that can be applied to them all,
is your view, and
it may be the view of others. But I would suggest it
ignores some fundamental differences between the voting
systems. IRV in
particular makes no pretence at complying with a range of
social choice criteria - it is a complete different kind
of voting
system.
I find this a really astonishing thing to say. IRV and all other ranked
choice systems ask for the same input from voters and produce the same kind
of output, namely a single winner. For you to say they differ so
fundamentally that no common standard can be appealed to looks an awful lot
like special pleading. And how can you argue that we should adopt IRV
instead of Condorcet or Borda or Bucklin if you have to common standard
from which to argue that IRV is better? Or is it only the criteria that
put IRV in a bad light that are irrelevant?
--
[EMAIL PROTECTED] 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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