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Re: Range Voting - the simpler better alternative to Condorcet voting

> http://rangevoting.org/vsi.html itself makes it clear that honest
> voting in Condorcet performs better than strategic Range Voting.

Right, there are a variety of asymmetric conditions under which
Condorcet may perform better than Range Voting.  You came up with one
such condition:

		     Condorcet with honest voting
		  Range Voting with strategic voting

although to be fair Condorcet would only win there with some
distributions of preference structures.

I came up with some others:

		     Condorcet with honest voting
       Range Voting with voters replaced by lobotomized monkeys

		     Condorcet with honest voting
	    Range Voting by with all desirable candidates
		       removed from the ballot

		     Condorcet with honest voting
	   Range Voting with ballots cast by hostile aliens

Seriously, it would appear that when people have attempted to make
fair comparisons, Range Voting has won.  Perhaps there were
methodological flaws in those studies, but if so you need to be a
little more precise about it.  For instance, perhaps as you argue
people would tend to attempt to vote strategically more with Range
Voting and less with Condorcet, although I'm not convinced of that.
But even if so, the question is what the magnitude of that effect
would be, and whether it would swamp the apparent intrinsic advantage
of Range Voting.  If you want to make a convincing argument, you'll
need to get a quantitative handle on these effects.

Regarding this "Condorcet discourages strategic voting" proposition,
that is---if you'll forgive me---hooey.  I'm living in Ireland and
there was a major election here just a few days ago using a Condorcet
system.  There was rampant strategic voting, and the newspapers had a
great deal of fun discussing it in the aftermath.  And Debian
Developers certainly do vote strategically in DPL elections, although
they wouldn't call it that; they'd call it "ranking people they really
don't want to see elected below wacko cranks and people they've never
heard of before."  Moreover, the lack of expressiveness of Condorcet
makes is impossible to cast a ballot saying: "I think A and B are
really good, with A just slightly better than B, while I think C and D
are both pretty bad, and E and F are both terrible."  In attempts to
shoehorn this into Condorcet people do things like putting X between B
and C or between D and E, but that only increases the expressive power
slightly and also does not actually have the desired effect.  Even
worse, Condorcet makes it impossible to say "dunno" about a candidate.

Bottom line: I don't think your flip canard actually outweighs serious
scientific attempts to figure out whether Range Voting is better than
Condorcet under realistic conditions.  I'm not saying the jury is in,
but what you said isn't much of an argument.  As far as I can see, at
this point there is pretty much zero serious argument that Range
Voting would be inferior to Condorcet for Debian elections, and some
pretty strong arguments to the contrary.

Barak A. Pearlmutter
 Hamilton Institute & Dept Comp Sci, NUI Maynooth, Co. Kildare, Ireland

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