[EM] Schulze's method fails Condorcet's Criterion, right?

[MIKE OSSIPOFF]

> > I've guessed and suggested that the uniform way would be to
> > use 0-info strategy. If that's it, then: Schulze's method
> > fails Condorcet's Criterion.
>
>So you say that due to your theory an election method meets
>the Condorcet criterion iff it always chooses the sincere
>Condorcet winner whenever a sincere Condorcet winner exists
>and the voters use a 0-info strategy.

That's my theory about what your theory is. Here's how I'd say it:
You determine, from the voted ratings, how many people vote which
candidate over which, and thereby determine if there's a candidate who
pairbeats each of the others. If so, then that's the candidate who
should win if the method meets Condorcet's Criterion.

Then, you say that, from those voted ratings, we should "get"
rankings. Then, from those rankings, we determine who wins. If the
candidate who wins isn't the same as the one that we found in the
previous paragraph, then the method fails Condorcet's Criterion.

That's what you said. Now here's where my theory about your theory
comes in: You still refuse to say how we "get" the way to make out
the particular method's method-specific ballot, based on the voters'
voted ratings. The unform rule for that. So my theory about that is
that your scientists determine, from a voter's voted ratings,
what that voter's 0-info strategy is, when voting with that method,
using that method's balloting.

That's my theory about your theory. Sorry I had to guess, but that
was necessary because you still haven't told us how you'd "get"
the way to mark the method's own ballot, based on the voters' voted
ratings.

>Could you please post
>an example of an election method that meets the Condorcet
>criterion due to your "universally accepted" theory?

My theory about your theory isn't universally accepted. In fact
I may be the only person who has written a theory about your theory.

But I'll tell you a method that meets Condorcet's Criterion, according
to my theory about your theory: Tideman(m).

You want an example? The example that I already posted is an
example in which Tideman(m) meets CC by my theory about your theory.
With Tideman(m), 0-info strategy is sincere, and so the candidate
who pair-beats everyone by the voted ratings will also beat everyone
by the rankings derived from those ratings by 0-info strategy.

This is not to be construed as advocacy for Tideman(m). Your way
of determining criterion compliances doesn't make any sense to me,
and so I don't use it to evaluate or choose methods. I prefer
Tideman(wv), SSD, BeatpathWinner, PC, Smith//PC, & Approval to
Tideman(m) because of the defensive strategy criteria that they
meet.


As you know, for determining methods' criterion compliances, I don't
assume any kind of balloting other than what the method actually uses.
Much simpler, much more justified. Here's how I write Condorcet's
Criterion:

If there's a sincere CW, and if everyone votes sincerely, then that
sincere CW should win.

A voter votes sincerely if he doesn't vote a preference that isn't
a sincere preference, and if he doesn't leave unvoted a sincere
preference that the balloting system in use would have allowed him
to vote in addition to the preferences that he actually voted.

[end of definition]

All pairwise-count meet CC by this definition, and all nonrank methods
fail CC by this definition. This is in keeping with the criterion's
intent and what we expect from it.

Mike Ossipoff

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