[EM] Kristofer reply, 4/14/12
km_elmet at lavabit.com
Tue Apr 17 04:21:20 PDT 2012
On 04/14/2012 09:43 PM, Michael Ossipoff wrote:
>> Yet that isn't absolute. Again, consider Burlington. The Burlington
>> voters, thinking they could now vote as they wished, ranked the
>> candidates in a manner suggesting a relatively close race between
>> the three major candidates. They didn't discover this was a bad idea
>> until after the election, but a Condorcet method would have given
>> them the right winner.
> Sure, Condorcet will only rarely violate FBC. It will only rarely
> make someone regret that they didn't favorite-bury. But I'm saying
> that the mere _possibility_ of benefit from favorite-burial has been
> (in staw-polling)
> and will probably often be, sufficient to make people favorite-bury,
> ranking compromise over favorite.
> You continued:
>> Given that observation, would not Condorcet acting properly have
>> encouraged the voters to vote in a non-compromising manner in later
> Some of them, sure. Not all of them. Not the diehard no-exceptions
> compromisors. The only thing that could assure them would be a
> method in which it was _obvious_ that it would be impossible to need
> or ever benefit from favorite-burial. A method in which it was quite
> clear that you have no reason to not fully support your favorite.
> You see, there are methods for which we can assure people that it's
> been proven that no one can benefit from favorite-burial.
Yes, such methods exist, but you have to give up quite a bit to get FBC.
In Approval's case, you have to give up the graduation of the ranked
ballot and do part of the parsing yourself. More generally (and less
controversially), FBC implies a constraint that limits the choices of
methods we might pick. I think that constraint is significant, as there
are few FBC methods out there.
So what I'm trying to show, or show the possibility of, is that FBC
might not be a make-or-break thing. You've said that Condorcet is fine
when people don't overcompromise, and you've given that as a reason for
why it works in an organizational context.
However, voters don't overcompromise just for the fun of it. Something
has told them that if they don't compromise for Dumb, Dumber might win.
The suspect party is obviously Plurality, and so you say that it might
also work where the people hasn't been taught to compromise early and often.
But it seems to me that this effect can work both ways. The Plurality
dynamic is that for every election where not compromising causes Dumber
to win, the people learn to compromise; but why shouldn't it go the
other way? "For each Condorcet election where voters that don't
compromise find that Smart still wins, they feel even less of a need to
We know from Burlington that compromise isn't absolute. In the 2009
election, voters voted in a way suggesting a close race. (Then IRV
punished them for it.) If the election had been Condorcet, the right
candidate would have won. Wouldn't that encourage those who didn't
compromise to keep not compromising, and suggest to the compromisers
that compromise wasn't needed? Couldn't that, after enough elections,
show the voters that they don't need widespread strategy?
FBC is obviously a much stronger assertion. When you're dealing with a
method that passes FBC, you know (and can tell the voters) there's
absolutely no need to betray a favorite. There's no need for the kind of
feedback I gave above. Yet if the scenario I gave is realistic, that
means one doesn't need to dismiss other methods like Condorcet for
> That would help, and maybe it would be enough to avoid a
> favorite-burial problem. But here, again, Approval is incomparably
> better, because it's so obvious that giving top (Approved) rating to
> your favorite can't possibly hurt your compromise, to whom you also
> give top rating.
> But what about a method for which it isn't even possible to ask
> people to take our word for that assurance? Methods like Condorcet,
> for which we have to admit that sometimes favorite-burial will save a
> compromise and prevent someone worse from winning.
> Without Approval's transparency and simplicity, FBC compliance might
> not be enough. But lack of FBC compliance certainly won't be enough.
Not on its own, obviously (or IRV would be better than Approval!). But
if the voters are like RBJ, for instance, they may prefer a ranked
ballot to an Approval or Range-type ballot; or they may think that (if
the concept was explained to them) the CW should always win because he
has a majority backing him against anyone else. Throwing away FBC and
not getting anything in return is of course silly, but throwing away FBC
and *getting* something in return might not be -- at least if FBC
failure need not be as serious as you say.
> You continued:
>> Or do you prefer the voting method to give an ironclad assertion
>> that there won't ever be a favorite betrayal problem, so you can be
> Most definitely. But it isn't I who must be sure. It's the
> over-timid, compromise-conditioned voter.
Can't he be convinced by experience? Even in Plurality, the right
condition sometimes comes by (e.g. the 1992 US Presidential election),
but each time, Plurality shows the voters they better compromise.
Perhaps one can show that in an u/a setting, Condorcet passes FBC; and
you could reason that when voters are no longer thinking in u/a terms,
they have already moved beyond Plurality-style reasoning. That might be
weak to the arguments I've given against IRV, though.
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