defend this:

[Mike Ossipoff]

It isn't difficult to find an example where Copeland (including
Regular-Champion) screws-up.

For instance it happens in an example that I've been using
for some time:

Sincere preferences:

40%: Dole, Clinton, Nader
25%: Clinton
35%: Nader, Clinton, Dole

We could write it so the Clinton voters are evenly divided
between Dole & Nader for 2nd choice, but for simplicity I
didn't write a 2nd choice for them.

Clinton is Condorcet winner. Regular Champion picks Dole.
The truncation by Dole voters has stolent he election for
their candidate.

How do you defend that?

How can you defend a method that can elect someone with
a majority against him, when he's the only candidate with
a majority against him?

As I've said, Condorcet meets the Truncation Resistance Criterion:

Truncation shouldn't be able to gain the election of an alterntive
over which a majority have ranked the Condorcet winner.

Copeland fails the Truncation-Resistance Criterion.

***

You've said that it means nothing to not be subject to truncation
strategy, and still be subject to order-reversal strategy. 
You said something to the effect: What good does it do to
be not subject to trunction, if the method is still subject
to order-reversal?

But truncation has happened in every rank-balloting I've conducted
or participated in, and will happen on a large scale in any
election. We've both agreed that order-reversal won't happen
on a scale sufficient to affect the election result.
If you change your mind about that agreement, then I remind
you that order-reversal is  quite risky and well-deterred,
and that it requires an organized devious strategic attempt,
while truncation can be done without any strategic intentions.

So your question is as if I asked: What good does it do to not
walk down the middle of a freeway lane, if not walking down
the middle of a freeway lane can't protect you from falling
meteorites?

***

Do you want something else to defend? Ok, how about the
example I posted, about the movie genres? I'll repeat it
for you, since you apparently haven't noticed it yet
(since you haven't defended Copeland in that example yet,
or even tried toi):

You're in a group that's decided to go to a movie, and to use
Copeland to choose which movie to go to. There are Westerns,
crime movies, & adventure movies. More voters like Westerns
than crime movies, and so all the Westerns beat all the crime
movies. Similarly the crime movies beat the adventure movies,
and the adventure movies beat the Westerns. And let's say
that some voters have truncated, and so we don't know if there's
a Condorcet winner.

So there's a circular tie. Let's say there are lots of crime movies,
and very few adventure movies. This gives the Westerns the
highest Copeland score, so the winner ends up being chosen
from the Westerns, for no reason other than that there are lots
of crime movies & few adventrure movies. Nonsense. Copeland
is nonsense. What kind of a way is that to pick a movie genre?

If it were parties, or candidates of various types, the
same thing could happen. Furthermore, a candidate could even
hire some people to run, on platforms or party affiliations
that will put them among the candidates whom he beats. Easy
Copeland points. He could also hire some people to run on
platforms or affiliations that would put them in a candidate set
that beats someone else, lowering their Copeland score.

***

Aside from that, if more than half of the voters say they'd
rather have A than B, and Copeland picks B, how do you defend
that, when there are other alternatives that _don't_ have
a majority saying that something else is preferable? Copeland
will even elect an alternative that is the _only_ alternative
to which a majority ahve voted that something else is preferable.
Defend that.

***

Mike





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