[EM] RE : Re: RE : Re: A few concluding points about SFC, CC, method choice, etc.

[Kevin Venzke]

Hi,

--- Abd ul-Rahman Lomax <abd at lomaxdesign.com> a écrit :
> At 04:29 PM 2/15/2007, Kevin Venzke wrote:
> >I would guess that most of our criteria *do* coincide with higher
> >utility. All things being equal you couldn't expect that a method that
> >fails majority favorite would produce higher utility.
> 
> I'm not sure what "all things being equal" means, particularly 
> because Majority Favorite is clearly suboptimal in some 
> not-too-uncommon scenarios, generally involving the majority having a 
> small preference for a candidate, with the minority having a large 
> preference *against* that candidate.

What I mean is, if you create two arbitrary methods, one satisfying
MF and one not, you should expect the first one to have higher utility.
It's true some methods might gain higher utility by peeking at the
majority's lower preferences. But other methods could have terrible
utility from penalizing the candidate with the most first preferences,
for instance.

My point is that I don't agree with the assessment that criteria are
being valued with no concern for SU.

> Range will uncover this, and select based on overall utility, if 
> voters vote sincerely. If they don't vote sincerely, results will 
> vary, but they won't be *worse* than Majority Favorite.

I don't see how it will necessarily not be worse than the MF.

> The Majority cannot fail to elect its Favorite unless it allows 
> another candidate some vote strength. If the Majority *strictly* 
> prefers its Favorite, it will prevail in Approval. By "strict" I mean 
> that it does not allow the expression of parity with another 
> candidate. That is, a majority bullet-votes for its favorite. Only if 
> some segment of that majority also approves another candidate can 
> another win.

Of course a majority can still win under nearly any method if they're
coordinated and realize they constitute a majority.

The SU criticism is that tempting voters to bullet vote in such a common
scenario will cause information on lower preferences to not be collected.

That is why there is so much concern about providing voters guarantees
about being able to vote sincerely.

> Of course, with Approval, there is no way to determine 
> from the votes if there was a violation of Majority Favorite; indeed, 
> it seems more likely, in general, that the Approval winner *would* 
> generally be the Majority Favorite.

Approval can only fail MF if more than one candidate has majority approval.
I don't know why you would guess that the more approved of these would
generally be the MF.

> >There are other issues besides utility of course... There's the question
> >of what the public will accept and understand how to use, and there's
> >all the questions of how to give the voter incentive to vote sincerely.
> 
> It appears from Warren's research, however limited it was, that 
> voters are quite likely to vote sincerely unless you give them a good 
> reason not to.

I generally assume that the result of an election is at stake. More 
specific reasons depend on the incentives of the method.

> > > It's
> > > *assumed*, very easily, that the majority choice is the optimum
> > > winner -- and therefore it is desirable to satisfy the Majority
> > > Criterion -- when this is certainly not clear enough to be reasonably
> > > an axiom.
> >
> >I think it's actually clear that the majority favorite isn't necessarily
> >the SU winner. I don't think it follows from this that it isn't
> desirable
> >to satisfy MF. It depends on what alternatives you have.
> 
> The MF winner can be a disaster, compared to a Range winner, in some 
> scenarios not too far from recent history. I don't see the reverse 
> being likely at all. That is, Range is only likely to elect other 
> than the MF when there is a *better* candidate.

That's not the only consideration though. If MF is failed, this creates
incentive to truncate, regardless of whether the result actually has an
MF.

So you don't have to believe the MF is always the SU winner in order to
decide that the criterion is desirable.

> >An individual person has a great advantage in measuring preference
> >strengths.
> 
> Certainly. However, businesses also need to make decisions based on 
> input from many people. Range Voting is not uncommon in those 
> situations. (Consider how many polls you've participated in where you 
> were asked to rate something on a scale of 1 - 10.)

Well, I've rated a lot of things 1-10, but usually these weren't 
competing options. And I don't remember any time where it was the case
that one of these options was going to "win" and have an effect on me.

Kevin Venzke


	

	
		
___________________________________________________________________________ 
Découvrez une nouvelle façon d'obtenir des réponses à toutes vos questions ! 
Profitez des connaissances, des opinions et des expériences des internautes sur Yahoo! Questions/Réponses 
http://fr.answers.yahoo.com