1CC definitions were faulty.

Mike Ositoff ntk at netcom.com
Sat Nov 14 23:33:42 PST 1998


As Blake said, the attempts that had been made so far, at the
time of his statement, to write a precise criterion based on
the 1st Choice standard proposed by David Marsay were unsuccessful.
I don't deny it.

But Blake seemed a little too optimistic when he said that
it was clear to him that a precise 1st Choice Criterion would
never be defined.

Plainly I can't claim that my several unsuccessful attempts
at that mean that I'm good at writing difficult criteria. 
Ordinary GMC is useful, but it's also quite simple, unlike
what one gets into when trying to write a 1st Choice Criterion.

The standard, as expressed by David is so obvious, and the
importance of not having to completely abandon our favorites
is so obvious & well-understood, that I greatly underestimated
the difficulty of writing a 1CC, so much so that several times
I mistakenly believed that I'd written a usable one when I
hadn't.

But with or without a precise criterion for it, the 1st Choice
standard's importance is clear. I've shown examples of Margins
making people have to abandon their favorite. Is a criterion
needed to prove that that's udesirable.

I've been the only person pursuing the effort to write a 1CC,
and maybe that gives Blake confidence that none will be written;
but even if I haven't demonstrated myself to be especially 
skilled at difficult criteria, don't celebrate prematurely,
Blake. The underlying standard is so important that the
effort will continue. There isn't really any question,is there,
that, with better attention to detail, without the mistaken
belief in the simplicity of the task, such a criterion can
be written.

Anyway, in the meantime, the criterion that I'd been calling
"LO2E", and one similar to it, will do fine. Earlier Blake
found a fault with LO2E, and I no longer have that letter
stored. I'm not being careless, and haven't found a logical
fault, but of course there could still be one.

These criteria will serve the purpose that 1CC was intended for,
putting certain methods' failings on a more precisely-described
footing (hopefully). I'm a little concerned that, since I can't
find Blakes letter about LO2E-2, that these criteria might
have a problem that I haven't found, but I'd like to post them
anyway, here, and in a separate message:

I'm writing them both in the weak form. The strong form is
gotten by replacing "over a more-liked alternative" with
"equal to or over a more-liked alternative".

A simple defensive strategy criterion:

A group consisting of a majority of all the voters, who all
vote a certain particular candidate A over a certain particular
candidate B, should have a way of voting that will ensure that
B can't win. Accomplishing that shoudn't require any members
of that group to vote a less-liked alternative over their
favorite.

LO2E:

Replace the last sentence with "Accomplishing that shouldn't
require any members of that group to vote A over a more-liked
alternative.

That change was added in order to lower the bar enough for
Condorcet(EM) to strictly meet the criterion, instead of
just to meet it for all practical purposes.

Mike Ossipoff




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