[EM] Participation & SARC

[Markus Schulze]

Dear Steve, dear Mike,

Steve wrote (5 May 2000):
> Markus wrote (5 May 2000):
> > Supporters of Alternative Voting usually claim that Alternative
> > Voting guarantees that a set of additional voters each with the
> > same sincere opinion can never be punished for going to the
> > polls and voting sincerely. They claim that - as Alternative
> > Voting guarantees that a vote of a given voter for a given
> > candidate will never be counted unless all those candidates who
> > are prefered to this given candidate by this given voter cannot
> > be elected any more - a voter cannot be punished for making an
> > additional preference. And they claim that this means that
> > an additional voter cannot be punished at all for going to
> > the polls and voting sincerely.
> > 
> > The participation criterion is the mathematical formulation of
> > this claimed property of Alternative Voting.
>
> Borda also satisfies participation.

Actually, Alternative Voting violates participation. But to be
able to check this, you have to find a mathematical formulation
of participation.

As far as I know, only positional election methods (e.g. Borda,
FPP, Random Dictatorship) meet participation.

******

Mike wrote (5 May 2000):
> Markus wrote (5 May 2000):
> > The problem is: To be able to compare sophisticated outcomes,
> > you have to make presumptions about the used strategies. It is
> > not easy to make non-trivial justifiable realistic presumptions
> > about the used strategies.
>
> Presumptions? Voters' common use of defensive order-reversal
> in Plurality isn't a presumption--it's a well-known fact.

Sometimes this strategy isn't available. Please read "The
Alternative Vote and Ethnic Accommodation: New Evidence from
Papua New Guinea" (Electoral Studies, vol. 16, p. 1-11, 1997)
by Ben Reilly.

In general, the availabilities and the costs of the different
given strategies depend very sensitively on the properties of
the society. Therefore it is neither obvious nor unique which
strategies are used for a given election method.

******

Mike wrote (5 May 2000):
> Markus wrote (5 May 2000):
> > I guess that you are talking about Albert Langer.
> > But remember e.g. that Lucien Saumur promotes
> > Smith//RandomCandidate.
>
> True. And so it could be of some interest how his method does
> by criteria generalized to cover random methods.
> But Smith//RandomCandidate isn't a proposal that we reform
> advocates are ever going to have to deal with as a competitor
> or a serious rival, if only because random selection would never
> be accepted by the public, or by the people who write media
> articles. It seems to me that RandomBallot did worse in Norman's
> simulation than any other method. RandomCandidate seems like it
> would surely do worse. Simulation results like that further clinch
> the public unacceptability of random methods. I personally don't
> have much objection to trying such a method, because eventually
> we'd get lucky and get a good President, and the public might
> find out that they like his policies. But as a proposal, it's
> out of the question.

Neither Steve nor I asked you to promote random election methods
in general or Smith//RandomCandidate in particular. We only said
that criteria should be defined in the probabilistic context so
that it is not possible for somebody else to claim that a given
strategical problem can be circumvented simply by using some
random mechanisms.

******

Mike wrote (5 May 2000):
> Excuse me, Markus, but what mathematical formulation is lacking
> in SARC? And will you please tell me what "non-trivial" means?
> Or maybe the way to word this question is: What is it about
> SARC that makes you say that it lacks a mathematical formulation
> that a criterion should have?
>
> And if you feel that some of my other criteria lack a necessary
> mathematical formulation, would you specify what it is about them
> that would make you say that they lack a mathematical formulation
> that a criterion should have.
>
> One thing I admit is that I still haven't put an extended
> "voting equilibrium" (extended to non-point systems) on a precise
> basis. So of course I can't write a precise criterion that
> speaks of that equilibrium. But I'd be interested in what
> you'd say that my other criteria lack, that a criterion needs.
>
> If you mean that all criteria have to be written in the stilted
> symbolic jargon found in some journal articles, then I'd ask
> who says criteria need that, and how would you show that they
> need that.
>
> If it's because spoken language can be ambiguous at times, I
> believe that it's possible to write something in ordinary
> language (as opposed to symbols borrowed from mathematics) in
> a way so that people know what it means. Surely that's the goal
> of language. And I've noticed that authors who use
> mathematical symbols still need lots of ordinary language to
> try to clarify what their symbols mean.
>
> Actually, I'd say the opposite: Criteria & method definitions
> that are written only in that symbolic jargon borrowed from
> mathematics are useless for showing to the people to whom
> criteria most need to be shown. Mathematicians can exchange
> symbols forever, but practical use of criteria & method
> definitions requires showing them to members of the public,
> members & leaders of organizations, etc.
>
> If there's an ambiguity in one of my criteria, then someone
> can point to it and ask me what I meant. I've tried to say
> them so that it will be clear what is meant.

I didn't criticize SARC. I only said that participation
isn't SARC.

Markus Schulze
schulze at sol.physik.tu-berlin.de
schulze at math.tu-berlin.de
markusschulze at planet-interkom.de