At 10:37 PM 5/18/2010, Dave Ketchum wrote:
I had written promoting Condorcet.
Kevin Venzke offered some objections, #1 is above, indicating that
ratings have the value of being more expressive. I responded to his
thoughts, also above.
Abd ul, who often writes usefully, wrote a book here, wandering into
various topics such as Bucklin.
My condolences. You were not forced to read it.
The upshot of my writing has been to note that there is no conflict
between Range ballot and Condorcet method, because a Range ballot can
be used to rank candidates and thus as a basis for condorcet analysis.
Bucklin is a method which, I've been noting, effectively uses a range
ballot to drive an Approval election, repeating this with lowering
approval cutoff. If Bucklin finds a majority, but not two majorities,
the Bucklin winner must be the Condorcet winner.
With a finer resolution Bucklin ballot, multiple majorities will
become less likely. Condorcet failure when a majority of the
electorate has approved the Condorcet winner, but approved another in
greater numbers, represents a small loss of utility, ordinarily, and
this is a classic solution where two propositions are considered for
Yes/No vote simultaneously, they conflict, and both pass.
The base topic is Condorcet. It would take a book to respond to all
your extensions such as IRV. Likewise I see no benefit in adding
Borda - Range/score is an adequate source for ratings.
From Wikipedia:
Condorcet: For each ballot, compare the ranking of each candidate on
the ballot to every other candidate, one pair at a time (pairwise),
and tally a "win" for the higher-ranked candidate.
You should know that the "opinion" of Wikipedia is not necessarily
any better than my opinion -- indeed, in some cases, it is my opinion
and I put it there --, and these articles swing with the wind.
The definition is badly written. It's not a definition, actually,
it's an algorithm, with missing pieces.
Range voting uses a ratings ballot; that is, each voter rates each
candidate with a number within a specified range, such as 0 to 99 or 1
to 5.
Or ranks the candidates, assuming that enough ratings are available
to do this fully.
In Condorcet the counting is of pairs of candidates so the
possibilities for A vs B cannot be other than A>B , A=B, or A<B - no
way to have a skipped rank.
But don't confuse Condorcet analysis with Condorcet method and
Condorcet ballot.
A Condorcet ballot can have skipped ranks. A Condorcet method does
not use them. Condorcet analysis of a Range ballot would assign no
meaning to the skipped ranks. Unless it was designed to do so: it
could do so, for example, to resolve condorcet cycles. Some Condorcet
methods, in effect, do this, with the "skipped ranks" being ranks
occupied by candidates not involved in the pair.
In Range the limits can be other than 0-99, but those are suitable for
the discussion.
Not if you are complaining about Range "forcing" you to make refined
decisions. Do remember, Approval is a Range method, with only two
ratings. 0 and 1, or No and Yes.
Dave, you apparently don't understand a good deal of what you read.
That's okay, take your time.
My point was about your use of "demanding ratings details," which is
not intrinsic to range methods. In particular, I've been pointing
out, Borda is a ranked method that is a Range method, and it becomes
full range if the method simply allows one to equal rank any two (or
more) candidates without disturbing the points given to other
candidates.
The topic is "ratings" and, Range being adequate for the cause, there
is no need to wander into other methods.
The point is that Borda is not an "other method," it is Range with a
peculiar restriction: no equal ranking allowed, and incomplete
ranking dilutes the ballot (with some rules).
You are showing, Dave, that you have completely missed the point.
Again, you use "must." No, a Range ballot can simply be a list of
ranks.
Such a list might be - but numbers would make more sense with limits
such as 99.
That would be a list of ranks, from 0 to 99. A Range ballot allowing
this would allow complete ranking for up to 100 candidates. Don't
want the sweat of deciding exactly where to rank each candidate?
Easy, just spread them roughly across the range. You are then voting
a Borda-like ballot, and you are fully ranking.
Frontrunner is in the middle? Okay, if you want to cast an effective
ballot, push the rating up -- and all rated above this candidate --
or push it down, and all rated below. It would be easier if you rate
frontrunners first, you can then spread remaining candidates through the range.
I do not recommend such high resolution Range. I'd be happy to see
Range 4, used as a ballot to feed a Bucklin set of rounds, with a
runof if a majority is not found. Very easy to vote, and a powerful
technique, much more flexible than straight Approval.
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