Re: Range Voting - the simpler better alternative to Condorcet voting
Let me see if I have this straight.
We would both agree that:
- Range Voting is more expressive than Condorcet. (In the sense that
it is possible for a voter who so desires to more precisely express
their true opinion.)
- Range Voting is simpler (easier to understand) than Condorcet.
- With honest voting, Range Voting beats Condorcet.
- With strategic voting, Range Voting beats Condorcet.
- When voters switch from being honest to being dishonest, the
performance of Range Voting degrades less than does the performance
of Condorcet.
So (aside from calling me names) it seems like your argument boils
down to the idea that somehow Range Voting causes voters to be less
honest than they are with Condorcet? And not just a little more
dishonest, but a *lot* more dishonest! And the reason you hypothesize
that this will occur is that Condorcet performs so horribly when
voters are highly strategic that they will recoil in shock at the
prospect and in reaction take a vow of utter honesty.
That's what I take it you mean by this:
> With the difference that with Condorcet, you can confidently say to
> voters: "if you lie about your opinions of the candidates when you
> vote, you are much more likely to hurt yourself than to help
> yourself, regardless of how you think others will vote."
although the statement itself would be a lie. (You could say it
"confidently" if you want, but it would remain false. Complete
honesty is not a stable strategy---in the Nash equilibrium
sense---with Condorcet. Or with Range Voting, for that matter. In
fact as Arrow's Theorem shows, there is no voting system which <etc>.)
You also write this:
> the fact is that with Range Voting, the *best* real-world outcome
> one can reasonably expect is total strategic voting on the part of
> the electorate
which is also false.
In practice, when actual experiments have been conducted, even when
they intend to vote strategically in Range Voting, voters do not
generally peg all candidates to min/max. Instead, they tend to give
intermediate values to intermediate candidates, but with a "push"
towards the extremes. This corresponds to being slightly strategic,
rather than fully strategic as assumed in the table I quoted earlier.
Such behavior would put Range Voting's performance somewhere near that
of "Condorcet without strategic voting" in that table.
There are several other forces that would tend to further discourage
extreme strategic voting with Range Voting in Debian, even aside from
whatever aspect of human nature seems to cause people in general to
exaggerate less than game-theoretically-optimal with Range Voting.
One such force is the Debian culture, which encourages honesty, albeit
at times perhaps brutal honesty. Another is that most discussion is
on open forums, so secret collusion would be difficult to arrange.
Yet others are that many of the top candidates are actually pretty
similar, and voters are not very rigid in their preference structures
and typically do not care so very strongly about who wins the DPL
election. Most voters would also probably not wish to publicly trash
(by rating with zero) candidates who are good and valuable Debian
contributors but happen to not be their favorite.
If you really want to resolve the question of what the best voting
system might be, instead of the current combination of ad homenim
attacks and falsehoods your posts on this topic have devolved to, I'd
suggest we try an experiment. One proposal: it would be easy to give
people the option of including a Range Voting ballot along with their
Condorcet ranking in the next DPL election. It would be very
interesting to see how the two correlate, both on the individual level
and on the ultimate decision level.
--
Barak A. Pearlmutter <barak@cs.nuim.ie>
Hamilton Institute & Dept Comp Sci, NUI Maynooth, Co. Kildare, Ireland
http://www.bcl.hamilton.ie/~barak/
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