[EM] (no subject)

MIKE OSSIPOFF nkklrp at hotmail.com
Wed Nov 2 13:54:45 PDT 2011



Kevin--

You wrote:

ER-IRV(whole) doesn't satisfy FBC. You may need to demote your favorite in order
to get a preferable elimination order.
 
[endquote]

How? Say that there's a particular candidate whom you need to have win. 

You can give him a vote by downrating your favorite in order to get hir eliminated soon,
so that your ballot will give a vote to the compromise. But you could also just give the
compromise an immediate vote, by ranking hir in 1st place. Why would you need to do otherwise
in order to help hir win?

You wrote:

Also, I do plan at some point to find an FBC failure of MMPO//MMPO//MMPO//etc.
I'm thinking it may require four candidates. My idea is that by lowering your favorite,
you knock your favorite out of a tie, so that only two candidates remain. But if there
were a three-way tie with no other candidates, MMPO would be stuck. So there
must be a fourth candidate available to be eliminated and allow the method to 
proceed.
 
[endquote]

Yes, when you mentioned that, it occurred to me that there could be such a scenario.

Anyway, I've abandoned MMPO because of its 3P failure.

You wrote:

Maybe I can reword slightly what Jameson said:
If sincere scenario (plus specific assumptions of voter sincerity) "S" can give rise to
cast ballots B, and a criterion C says S must have outcome O, then any method is 
going to have to select outcome O whenever the cast ballots are B. The criterion in
effect is requiring this, even when the scenario isn't S.

[endquote]

Rewording it in English would be preferable.

But let me try to answer anyway:

"S" represents a scenario in which some voters are stipulated to vote sincerely, correct?

Yes, if something has been stipulated about their preferences, and they're stipulated to vote sincerely
then yes, that implies something definite about their votes.

And the requirement requires that those votes produce (or don't produce) some particular outcome.

But what makes you think that any voting system must produce the same outcome, given the same 
criterion-premise? Big claims like that require verification. Surely different methods can give
different outcomes, with the same ballots, no?

Or are you saying that the criterion requires that? Of course it does. Given a certain premise, the
criterion requires something about the outcome. All criteria require that. That's the nature of criteria.

That's true with votes-only criteria, and it's also true with my criteria. What's the problem with that?

I suggest that your error is in not realizing that the premises of my criteria indirectly stipulate 
something about votes.

As I said in the posting that you're replying to (and already in this one too), 
if a voter is stipulated to have certain preferences, and to vote sincerely, then
that says something about how s/he votes. That's what you're missing. My criteria (indirectly)
stipulate how people vote, just as do votes-only criteria.

What do you mean when you say "even when the scenario isn't S?  If "S" represents a scenario 
meeting the stipulations of the criterion's premise, then the criterion only makes a requirement
when those stipulations are met. It says nothing about any other scenario. That's true of all
criteria, not just mine.

No criterion, including mine, says anything about what should happen when the "scenario" described
by its premise-stipulagions doesn't happen.

You're might well be right about MMPO not meeting FBC. 

You _weren't_ right Bucklin(= whole simultaneous)
not meeting FBC, because you were thinking that FBC requires that no one need to 
vote someone equal to their favorite. Actually, FBC requires only that
no one need to vote someone _over_ their favorite.

You suggested that there could be a scenario in IRV(= whole) where you need to get your favorite eliminated
quickly to help a compromise. Why? You can give a vote to the compromise immediately just by
ranking hir in 1st place, along with your favorite. You can't give more than one vote to a candidate.

Returning to my criteria, which stipulate preferences and relationships between voting and
preferences, 

You said:

It's like how SFC is supposed to protect sincere CWs, but in practice it ends up 
also defending some candidates who just look like they *might* be sincere CWs.

[endquote]

Irrelevant. Maybe you mean that, in an actual election, from the election-results, votes and winner, we
can't tell whether my criteria's premises have been met. So what. How often do we use criteria by
applying them to actual election results? Criteria are about the question "Could this happen?" Whether or
not we can tell whether it happened in a particular actual election is irrelevant. With any criteria, not just
mine, we judge a method by whether, given the criterion's premise, some particular outcome could or must happen.
Period.
 
Yes, SFC protects sincere CWs. Do SFC complying methods protect other candidates who don't
have a majority defeat (and, in that way "look like sincere CWs)? Sure. What's the problem
with that?
 
Mike Ossipoff

 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.electorama.com/pipermail/election-methods-electorama.com/attachments/20111102/8b2c9bd1/attachment-0004.htm>


More information about the Election-Methods mailing list