Seems that some are so lacking in understanding Condorcet that they
fear it. So, a couple basics:
. The voter can rank such as A=B=C, saying exactly equal approval of
these three over all other candidates. This has the same effect as it
would have in true Approval.
. The voter can rank such as A>B>C, approving these three over all
other candidates. Here the ranking reads as A>B, A>C, and B>C for
detailed liking among those ranked..
On Jun 9, 2011, at 8:04 PM, Kevin Venzke wrote:
Hi Juho,
--- En date de : Jeu 9.6.11, Juho Laatu <[email protected]> a
écrit :
No, I wouldn't say that. I do think there are methods
that offer two
bad options and one of them is burial, though.
(There is no working strategy, but there are some
options??)
Absolutely. I'm being honest when I say I don't know how I would vote
in the simplest election. If all I know is that my preference order is
A>B>C and the frontrunners are A and B, what should I do? Let's go
over
it.
1. Vote sincerely, A>B>C. On a gut level I *don't want* to do this. B
is the candidate I am trying to beat. Why do I want to help him beat
C?
This can actually help B and it will never help A. I feel like a
sucker
if I expose myself to this risk for no possible benefit. I do not need
to know whether there is *really* a threat; it makes no sense for me.
You are saying that you are not sure you really voted what you
thought. Your words imply A>C would be truer sincerity - even A>C>B
would be nicer to B than he deserves - leaving B unranked would place
him equal to all others you leave unranked.
2. Lie, and vote A>C>B. Now I'm a bad guy who you think must have some
strategy in mind for picking this manner of voting. If I thought B
voters
were going to use this same strategy against me then in voting like
this I might just be defending myself. But outside of that
possibility,
maybe I just don't have any good options?
3. Bullet-vote for A. Nope, not if this is margins. That's just
splitting
the difference or flipping a coin. It's childish to vote like this.
But actually, I think I might vote this way, just because I wouldn't
have
to feel like either a sucker or a jerk for doing it.
Depends on what you think of C. Above you were helping C as second
choice after A; here you would demote C to unranked.
What? The voters are participating in repeated
polling, and have the
ability to see not just each poll's outcome but what
they could have
accomplished by doing anything else. Buriers see that
burial is an
advantage if the opposing side is sincere. When
pawn-supporting voters
compromise, the buriers have no reason to revert to
sincerity. (They
don't even know what sincerity is.)
You seem to assume repeated polling, sufficiently accurate
results, unchanging results, similar results from all the
polling companies, no intentionally misleading polls, no
meaningful changes in behviour before the election day, no
interest to give false information in the polls, maybe no
impact of planned strategies on the voting behaviour of
others, good enough control of the strategists (if needed).
Your description isn't that unfair. Changes are possible, but most
methods
and scenarios become pretty stable.
I am skeptical about the concept of intentionally misleading polls,
especially when the polling doesn't work as predictably as in FPP,
where
the belief that candidate X is strong is generally going to help X.
I don't really believe in "planned strategies" that are kept secret.
If
this is really a problem, then, ok, my simulations aren't covering
this.
If what you're asking is whether this could be
thwarted by not revealing
any polls to the voters, then I can't address that. My
voters have to
have polls in order to learn how the method works.
In some methods like Approval poll information is needed to
cast a vote in line with the typical recommendations on how
to vote (= approve one of the frontrunners etc.). One could
also have Approval elections without such information. In
that case voters would not vote strategically but would
maybe mark those candidates that they approve for the job.
In Condorcet the basic assumption is however that voters
can sincerely rank the candidates. Doing so tends to improve
the outcome of the election. The strategy of making polls
unreliable may thus improve the outcome of the election.
Yes, if you can make polling unreliable, it would be very irritating
when the election method is Approval or FPP, and it might help
Condorcet.
, the defensive strategy used in response
seems to be
compromise strategy, as opposed to truncation
or
burial-in-turn, things
that risk ruining the result.
That is, there are voters who know they can't
expect
to gain anything
by voting sincerely, so they play it safe.
I agree that there are situations where some
voters will
not lose anything by using whatever strategy with
even some
infinitesimal hope of improving the outcome (e.g.
when they
know that otherwise the worst alternative will
win). But how
can they know (based on the limited available
information)
that sincere voting will not help them? Do they
know for
certain that some strategy is more likely to help
(and not
harm) them?
I'm talking about voting for a sincere favorite who is
not believed to
be a contender. If that candidate can't win, and could
be a liability,
then you could logically decide to dump him.
Ok, with favourite candidates that have no chance of
winning one can usually do pretty much whatever one wants.
That typically does not make the results of this election
better nor worse.
It should also be a *design goal* that this does not make the
results of
the election better or worse.
"whatever one wants" is true for such a favorite. You still have a
chance to affect who wins.
Often it makes however sense to make the
result as favourable to this favourite candidate as possible
since there are also secondary targets like helping this
candidate win in the next elections or just showing how much
support this line of thinking has among the electorate.
Yes, it's possible. I don't see a way to incorporate that
experimentally.
This is polling class data for such secondary targets.
So I expect that methods with greater burial
incentive
will just have
more (voted) majority favorites
I didn't quite get this expression. Would this be
bullet
voting by majority or what?
, and candidate withdrawals
Does this mean having only few candidates or
ability to
withdraw after the election and thereby influence
the
counting process or...?
What I'm saying is that methods with greater burial
incentive will
probably see supporters of pawn candidates stop voting
for those
candidates, and those pawn candidates would probably
drop out of the race
more often. (I think that compromise incentive and
nomination
disincentive go hand-in-hand.)
Ok, if there were such threats.
Hopefully from my first comments of this mail it's clearer what kind
of
threat I have in mind.
This is as opposed to the theory that methods with
great burial incentive
will see a larger number of train wreck outcomes as
voters play chicken
with each other.
I didn't quite catch what the impact of this to
the
usefulness of the reduced poll information based
defensive
strategy would be. Could you clarify. Did you say
that
already very rough information on which candidates
are the
frontrunners would give sufficient information to
the
strategists to cast a working (=likely to bring
more
benefits than harm) strategic vote (in Condorcet
methods in
general or in some of them)?
The relevance is more to the question of defensive
strategy under
Condorcet methods, than to your proposal.
Note that I proposed a preemptive defensive strategy to be
applied instead of concrete ones. I don't really like the
idea that people would start falsifying their preferences in
the actual election in order to defend against actual or
imagined strategic threats.
Haha. Every method has this problem to some extent, nothing to do with
burial even.
Truncation is one typical
strategic defence in some Condorcet methods. I prefer poll
level preemptive defence to this since that way we can avoid
e.g. Condorcet becoming "more plurality like".
If it works, sure, but if it doesn't, I would guess margins is the
"more plurality like" in the sense that the winner's first preference
count will probably be greater.
Truncation is often useful, apart from possibly being called a defense.
Dave Ketchum
I do believe that rough information on the
frontrunners is enough to
tell you *who* to bury, if you were going to
Yes, there is no point in burying anyone else but those
that are ahead of one's own favourite. The information on
which candidates are about to beat one's favourite should
however be correct with good probability.
I hope we are fortunate enough to have such a concern.
, and also who might
consider compromising to avoid a risk.
I'm afraid this information is already quite difficult to
collect and may not be very accurate and reliable.
This refers to the supporters of pawn candidates, so to my mind it is
almost just the inverse of who are the frontrunners.
I am mostly concerned about burial in methods that
seem to encourage it
without voters even having a specific plan.
I wonder where the accurate line goes on which Condorcet
methods are vulnerable to burial and which ones are not :-).
I do not know, but I have an interest in the question.
I'm afraid that in Condorcet methods there might be many
voters that rank their worst competitor last in the (not
very well founded) hope of improving the results from their
point of view :-).
More seriously, maybe some concrete written rules to voters
on how to bury in Condorcet elections (on in some Condorcet
version) would demonstrate that poll information can indeed
be efficiently used by regular voters in some real
elections. I tend to think that in many environments burial
would not be a problem, and in line with this mail thread,
maybe one could simply weaken the available poll information
and education of the voters if strategies start appearing.
If the nature of burial is that nobody thinks to do it without some
kind
of plan, then I am not nearly as worried about it. But since I myself
am not sure what I ought to do when I "can't" use defensive truncation
anymore, I am concerned.
Kevin Venzke
----
Election-Methods mailing list - see http://electorama.com/em for list info
