[EM] Comment on MJ discussion

[Michael Ossipoff]

Kristofer said:

As someone thinking MJ could be a good idea, I suppose I should explain
the reasoning.

MJ uses a grade ballot instead of a yes/no ballot because it encourages
comparison to a common standard.

[endquote]

Exactly. Your letter-grades encourage sub-optimal voting.

Kristofer continued:


 That is, if the voter is faced with the
question of assigning each candidate a grade, and the grades are well
defined (each person knows what a B means), then the voters will grade
according to that common standard. This means that MJ passes IIA: since
the grades are common, a candidate dropping out doesn't change the
grades of the other candidates.

In contrast, Balinski & Laraki has experimental evidence that suggests
that when the ballot is a yes/no (Approval style), voters are much more
likely to act in a comparative manner - which is to say that they
compare the candidates to each other, rather than comparing every
candidate to a common standard. When they do that, B&L says, Arrow's
impossibility theorem creeps back into the picture and you lose IIA
compliance.

[endquote]

So B&L have discovered that Approval fails IIAC? :-)

Here's the brief, simple, precise and clear IIAC definition that i've heard:

Removing a losing candidate from the ballots and from the election,
and then re-counting the ballots, shouldn't change the winner.

Approval and Score pass.

[end of IIAC definition]

It sounds as if you, and B&L, must be using a more complicated and
wordier definition of IIAC.

Would you like to post it here? Don't forget to post it complete and precise.

> If a voter grades a candidate as 'B' rather than 'A', the voter has
> detected some flaw in the candidate and is expressing it in the grade.
> To treat that voter's vote as simply above or below the median is to
> debase it. Why should the voter take the trouble to assign a grade if
> it's only use is to place the vote in the higher or lower half of the
> votes cast?

Kristofer said:

There are three reasons for this.

The first, let's call it "flexibility of meaning". Taking the median
means that the system doesn't impose any particular meaning of the
grades. It doesn't matter to the method *how much better* an A is than a
B, because it'll still work. Thus, the method doesn't require the voter
to rate the candidate. He can simply choose from the grades.

[endquote]

If you rate a candidate non-extremely, then you won't know whether
you're pulling hir up or down.

You might very well not be having any effect on the relative final
scores of a particular candidate-pair. Or you might be affecting their
relative standing oppositely to your voted preferences.
And, as I said, you might be helping someone you've rated lower
against someone you've rated higher. A ballot that rates Favorite at
top, and Compromise somewhat lower, could change the winner from
Favorite to Compromise. That sort of thing won't happen with Approval
and Score.

Kristofer said;

The second is strategy resistance. By taking the median, anybody voting
higher than the median will accomplish exactly the same thing by voting
highest possible, and anybody voting lower than the median will
accomplish exactly the same thing by voting lowest possible.

[endquote]

Meaningless, because the voter doesn't know where the median is.

Kristofer continued:

So in that
sense, there's no reason to vote bottom or top

[endquote]

Nonsense. The only way to reliably help a candidate is to vote hir at
top. The only reliable way to help your preferred candidates against
less preferred candidates is to rate the preferred at top, and the
less preferred at bottom.

Kristofer said:


; and if honesty is the
default position, it will take very many voters indeed to make strategy
actually have an effect, compared to rated-ballot systems.

[endquote]

Kristofer wants to make a virtue of unresponsiveness.

If people are rating X above where X's median previously would have
been, then it doesn't matter how high they rate hir. That's  what
Kristofer is touting.

He's forgetting that the voter doesn't know where X's median is.

The MJ-advocates' main belief and argument is that MJ discourages
optimal voting, because sub-optimal voting might or might not achieve
the same result.

...might or might not have any effect at all, regarding a
pair-comparison that's important to you.


Kristofer continued:

A
strategizing voter might still get some probability of a better outcome
by voting top on some candidates and bottom on others

[endquote]

That's called optimal voting.

Kristofer continued:

, or by voting a
particular way if he knows what the median is, but these qualifying
"ifs" would keep most ordinary voters from doing that.

[endquote]

Excuse me, but there was no "if" in your earlier statement, about
optimal extreme voting.

Kristofer is getting it backwards. If you rate X at top and Y at
bottom, you're reliably fully helping X against Y. There' s no "if" or
"maybe".

If you do otherwise, that's where you get "maybe".

We live in a technological society. Among some people, there's a
tendency to worship science. Anything that;s more complex is felt to
likely be better. That's MJ's mystique.

It's just complicated enough that it's easy to obfuscate (for oneself)
what's going on, and whether it's an improvement. Given the need to
worship technology, and the consequent love for complexity, it's easy
to be tempted to deceive oneself that MJ must be doing something
good--even if one can't say what it is.

So I suggest: If you can't clearly articulate how MJ brings
improvement, and if you can't answer my criticisms of it, then maybe
you could reconsider your beliefs about it.


Third, the median satisfies majority by grade. If a majority says X has
grade B, and B is the highest grade used, then X wins. This is a
protection against "crankiness", as someone (I don't remember his name)
proposing median voting for budget calculation problems said. If you use
the mean, then someone who is very loud will get his say
disproportionate to his number. Range voting advocates say this is an
advantage, but in a political system, if a majority gets overruled, it
could easily try to regain its "right" by less peaceful means.

Thus, if
point #2 is about resistance to deliberate strategy, this is about
resistance to outliers otherwise.

[endquote]

This time, then, Kristofer is assuming sincere voting. But why should
anyone rate "sincerely" (utility-proportional)? Why, when it isn't in
their best interest.

MJ advocates seem to have a _moral_ belief about sincerity. They
believe that it's somehow wrong, or dishonest, to vote optimally, in
one's best interest.

Hence the MJ-ist's desire to discourage optimal voting. Of course you
won't discourage it, even if you try. As I suggested above, the fact
that sub-optimal voting might or might not give the same result hardly
discourages optimal voting.

And MJ-ists haven't justified their moral stand about "sincere
voting". Why (in their mind) is it important to discourage optimal
voting, and try to make people vote utility-proportional?

Mike Ossipoff