[EM] The "Turkey" problem

Tue May 27 11:14:04 PDT 2003

Dave,

We're not on the same page just yet...

 --- Dave Ketchum <davek at clarityconnect.com> a écrit : 
> > If they are truly worth zero to you, then it makes no difference whether
> > you truncate them or order them randomly.  You merely have to fill in
> > more bubbles in the latter case.
> 
> Go back and look at the example we have been using.  There was no 
> truncation, and B won because all agreed B was not the worst candidate.
>       If all had truncated, there would have been a tie between A and C.
>       If A and C truncated, B voters would have decided which of them won.

The only thing relevant to the truncation issue is that last line.  If
A and C truncate, B voters decide the winner.  But in the example, A and 
C are both worth 0 to those voters, ergo it makes no difference TO B VOTERS
how they order them.

It's true that B won because all agreed B was not the worst candidate.
But on the whole (not just from individual perspectives), B CAN be
called the worst candidate because he minimizes (total worth / number
of voters) by far.  He is a turkey/rogue/lemon.

Again, I'm not trying to convince you that this is important, only that
it is possible.

> > 
> > We don't seem to differ much here.  My point was that there is no gain
> > in truncating when the worths are not the same.  May I ask: Do you think
> > that disliked candidates are all worth 0?  It sounds like you do.
> > 
> 
> No, I am saying that, PROVIDED I see them as equally bad I properly 
> truncate; if I see differences in value I VOTE what I see.

OK.  That gives me less to type.

> 
> > 
> >>Coming back to "universally disliked", if this label is true this 
> >>candidate is not going to get ranked high by enough voters to win.
> >>
> > 
> > See below.  A CW doesn't have to be ranked high, he just has to be
> > ranked HIGHER.  There are no guarantees about how much he is actually
> > liked by anyone.
> 
> In the examples B and D get few, if any, votes as best, but ZERO (repeat 
> ZERO) voters assert that they are the worst available.  B and D win 
> because a LOT of voters agree they are not the rottenest lemons in the pot.

Agreed.  I'm not arguing about why they won.  I'm just saying they
could still be lemons.  COULD.  Actually, the last sentence looks like
it concedes that point.  (That would be significant because it's the only
point I am trying to make.)

> 
> > 
> >>>Even if the voters are agreed, nothing inherently prevents the CW from being
> >>>the best of the worst lemons.  The point is that Condorcet makes no
> >>>guarantees about the value (avg worth to each voter) of the CW, and
> >>>that's what the "turkey problem" is.  If that doesn't bother you, that's
> >>>fine.  But I'm not so sure it's an "unreasonable fear."
> >>>
> >>>
> >>If the candidate field is all lemons you might get there; if there are ANY 
> >>candidates with some attractiveness they should attend to the worst lemons.
> >>
> > 
> > In the scenario envisioned, the candidates who are not lemons are a "love 'em
> > or hate 'em" deal, who all have more opponents than fans.  I'll spell this out
> > for you:
> > 
> > 34: A>D...
> > 33: B>D...
> > 33: C>D...
> > 
> > D is the CW.  We cannot discern whether D has the greatest worth (possible)
> > or whether he's an incompetent but innocuous fool and everyone knows it 
> > (also possible) or whether no one knows much about D but would rather take
> > their chances with him than with the two "major" candidates they know they 
> > don't like.
> 
> NONE of these voters rank D as highest possible, or as lowest possible. 
> They elect D because all of them agree that D is better than the 
> competition though, for each of the others, a minority likes their 
> favorite better.

Agreed, again.  I'm saying that in ABSOLUTE terms (adding up worth),
from a GLOBAL perspective, D could be the worst.

> > The topic IS Condorcet.  I am not talking about a different ballot.
> > I am specifying candidates' values to voters in terms of numbers.  I
> > am reading their minds, not asking them to estimate their own feelings.
> > 
> > I can't believe you don't see the motivation for this.  I'm trying to
> > persuade you that a generally disliked candidate can be the CW.  How
> > on earth can I give you an example of that without a measure of
> > "dislike"?
> 
> Let's try it a different way.  It does not matter whether I like all the 
> candidates or dislike them all as lemons.  I have to rank highest the one 
> I like most or dislike least.  "Generally disliked" does not seem like a 
> useful label for a candidate some rank high (and therefore has a chance to 
> be CW), though it could apply to the collection I have to choose from.

Ok.  I agree with you, that given the rules of Condorcet, the voter has
absolutely no reason to think about absolute worth, or preference
priorities.  The "turkey problem" is not a strategy problem.  It is
a useful and interesting concept only when comparing Condorcet to
electoral methods that don't have it.

> In an election we are trying to read the collective voter minds.  It 
> matters what the sum is, but not any individual voter's opinion.

But this sounds like you are taking my position.  If you sum up worth,
B is the worst candidate, and D could potentially be.  (Note that I am
not claiming that B and D shouldn't be elected.  In the ABCD election,
I am not at all sure I want to elect someone other than D.)

> Neither do we as vote counters get to weigh votes according to what a voter 
> thinks - all we have is what they say.

Agreed, given Condorcet as the method.  Other methods (such as Approval)
require the voter to consider candidates' worth, just to be strategically
efficient.  In other words, we can get useful information even if the
voters have no interest in being sincere.

> >>Given this confusion, I will have little to say about other paragraphs.
> > 
> > So have I ameliorated the confusion?
> > 
> Yes, for you seemed to know why voters voted as they did, and now say you 
> are reading Condorcet ballots and can only guess.

Come on now.  I can tell you how the voters feel because I'm the one
designing the scenario.  I'm not looking at the ballots and guessing.
I'm giving you a worst case scenario, that's it.

Kevin Venzke
stepjak at yahoo.fr

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