[EM] MMPO and FBC. Votes-only criteria.

[MIKE OSSIPOFF]

(Sorry to change the subject line, but this one is much easier to write.)


Kevin wrote:

Mike's method is Condorcet//MMPO//Condorcet//MMPO//etc.

[unquote]

No. I initially defined such a method. Then I said that I propose only
MMPO (applied to its own ties), because FBC is more important than Condorcet's
Criterion. I said that, as I define MMPO, it _doesn't_ include a CW search, because
I want FBC compliance.

I propose MMPO//MMPO//MMPO...

Kevin wrote:

However, even if Mike's method were just MMPO//MMPO//MMPO//etc I
still highly doubt that would satisfy FBC, because the candidate
eliminations and recalculations make it unclear that votes will work
as expected. I don't know how to say this much more clearly than that.
But let me ask you, how many FBC-satisfying methods involve eliminating
candidates and then recalculating scores once those candidates are
removed? Not a one.


[unquote]

I mentioned and answered that argument yesterday on EM.

I'd say it again today, but I don't have long on the computer today. I refer you to
my posting yesterday.

Kevin wrote:

Hypothetically, off the top of my head, lowering your true favorite
could remove him from a three-way score tie which then (as a two-way)
is resolved for one of your "other" favorites, whereas the three-way
contest is resolved for a disliked candidate. 

If a compromise (C) could win in a tie, but your favorite (F) couldn't, that must
be because C has lower maximum pairwise opposition (MPO) than F.

But, if that's so, then why do you need to vote C over F, to get C into a tie?

I'll be visiting, staying with, relatives this weekend, and I may not get much, if any,
time on computers this weekend.  For instance, today there's only time for this one posting.

Quinn said that criteria cannot mention sincere preferences.

He neglected to say why he thinks that.

What dictionary is he using?

Look up "criterion". It's a standard for judgment of something. Period.

Someone could say that a votes-only criterion, but not a preferences criterion, can be
used to detect noncompliance in an actual election.

Really? What criterion is shown to be violated, by Plurality election results?

Anyway, we don't use criteria in that way, citing actual examples of failure. We speak of what _could_
happen. That can be done just as well with criteria that aren't votes-only.

Did you know that Plurality meets the Condorcet Criterion?

It does, if we use a votes-only CC definition.

If for every y not x, more people vote x over y than vice versa, in Plurality, then x must win.
Plurality meets votes-only CC.

You might object "But the criterion says "rank" instead of "vote". 

If you vote x over y in a 3-slot ballot, everyone would agree you're ranking x over y.

What justification is there for arbitrarily saying that that isn't so with a 2-slot method such as
Plurality?  In Plurality, you're allowed to rank one candidate over the others.

Look up "rank" in a dictionary. It says what we'd all expect,what rank means to us all.

In Plurality, you're ordering one candidate above the others, giving hir a higher position than the others.

But if you still want to say that votes-only CC says "rank", and that somehow doesn't apply to Plurality, then
you're saying that votes-only CC can't apply to Plurality. Plurality doesn't fail it.

Votes-only CC, then, applies only to one class of methods.

You might say that's ok,because we already know we don't like Plurality, and none of us are
advocating it. But what about Approval? It, too, meets votes-only CC, unless you deny that "voted for" and 
"not voted for" are not different hierarchial levels (ranks). And if you say they aren't, then, again,
votes-only CC can't apply to Approval. Can't compare Approval and Condorcet.

My criteria apply seamlessly to all methods, and can compare any and all of them to eachother.

Votes-only criteria don't work.

By the way, Plurality meets Minimal Defense too.

Mike Ossipoff






Mike Ossipoff 		 	   		  
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