[EM] Remember Toby

[Jameson Quinn]

Message contents:
Section 1. When *isn't* SODA "more condorcet compliant than condorcet
methods"
Section 2. Smoke-filled rooms?
Section 3. What are we looking for, anyway? (in this thread)


*Section 1. When isn't SODA "more condorcet compliant than condorcet
methods"*

2011/6/4 <fsimmons at pcc.edu>

> For the benefit of those who are advocating ranked ballots in order to
> achieve Condorcet Compliance,
>
> note well that Jameson has a good argument that SODA, a simple method that
> uses only a Plurality
> style ballot, is more Condorcet Compliant than most well known Condorcet
> methods.
>

I believe that is true in a practical sense. However, I should note that I'm
not claiming that SODA achieves the impossible. As with other methods,
(attempted) strategy could spoil its condorcet compliance. I'll explain how,
and why I think that wouldn't happen.

First off: I'd like to note that I'm mostly worried about burial strategy
here. Generally, favorite betrayal strategy is useful to break an honest
Condorcet cycle to your advantage, while burial is useful to create a false
cycle which gives you some advantage. Since I think that honest cycles will
be rare, I'm more worried about the latter. Also, psychologically, most
people have a much higher propensity for burial than for favorite betrayal.
At any rate, in all the discussion that follows, I will assume that there is
an honest pairwise champion (CW).

So, in SODA, burial/truncation is still possible in several ways:
1. A candidate could cause a cycle through burial, and thus avoid the
(known, unique, strong, stable) Nash equilibrium for the honest pairwise
champion. However, that can only work to their advantage if the other
candidates actually believe that the false, strategic preference order, or
if they manage to exploit a dishonest strategic mistake by another
candidate. I believe that high-profile frontrunner candidates could not
plausibly claim a false preference order, so this strategy would be
ineffective.
2. Individual voters could use truncation (not burial, because it's
approval). For instance, voters could prevent their votes from being
delegated in order to engage in games of chicken to ensure that their
preferred near-clone was elected. This is a fundamentally unnecessary risk,
however. The near-clone with an honest lead does not need such tactics, and
the near-clone who is behind will probably need a dangerously large number
of voters to do such tactics. I don't see how this could be coordinated on
an effective scale in real life without backfiring.
3. Individual voters could vote for "false flag" minor candidates whose
honest preference ordering happened to be the strategic burial ordering that
they sought. I find this totally implausible, though; this requires a level
of cold-bloodedness and sophistication that only a tiny portion of people
have.

So when *is *SODA voting more condorcet-compliant than Condorcet methods?
When there is an honest pairwise champion; most voters bullet vote, allowing
delgation; and no frontrunner candidates (those with a chance of winning)
can plausibly claim a false preference order. *I believe that these three
conditions will hold most of the time.*


*Section 2. Smoke-filled rooms?*
*
*
Some people on this list have said that they don't like asset-inspired
methods like SODA because of the "smoke-filled room" scenario. That is, what
if you voted for someone who eventually, in some crooked deal, ended up
giving your vote to your least-favorite candidate? Certainly, I'm sure some
UK Lib Dem voters might feel that way about Cameron, so it's not a crazy
idea. There are at least 4 reasons that I think this fear is unrealistic;
I'll list them from weakest to strongest.

The weakest reason first: hopefully, your favorite candidate will be someone
you can trust. Sure, Nick Clegg might have betrayed some part of his base;
but in SODA voting, that part of his base who didn't trust him would have
been free to choose a different, more-trustworthy candidate, without fear of
FPTP making their votes irrelevant. I find some comfort in this argument,
but this reason alone wouldn't convince me to trust SODA.

Second, there is the fact that candidate's preference orders must be
announced in advance. Sure, that doesn't stop candidates from being
deliberately unstrategic in order not to help a higher preference beat a
lower preference, but that would be rare, and despite this, you can still
absolutely guarantee that your vote will not actually provide the winning
margin for that lower preference.

Third, the point of SODA is that candidates' post-election strategy is done
with perfect knowledge of the number of delegable votes and preference
orders of the other candidates. This perfectly transparent situation is the
exact opposite of a smoke filled room. As I've already said, it means that
if there is an honest pairwise champion, then there will be a known, unique,
strong, stable, Nash equilibrium where that champion wins. That's the gold
standard of game theory. With such clarity, I don't see how back-room
deal-making has a chance.

But fourth, and most important of all: in SODA, the vote delegation is
optional for the voter. If you don't want your vote to go to your
least-favorite candidate, then don't bullet vote. If you only want to vote
for one, you can make your vote non-delegable by voting for a blank or
invalid write-in. End of story.

And delegation is not all downside. Remember, by voting a delegable bullet
vote, you are not just giving your voting power to a candidate, you are in a
real way letting them speak for you too. A leader/spokesperson with 20% of
the vote would be much harder for the media, and the eventual winner, to
ignore, than 20% of the voters who (in plurality) simply hold their nose and
vote for one of the two main parties. Again, the point is that SODA gives
you more voice and more transparency, not less.

*Section 3. What are we looking for, anyway? (in this thread)*

If this whole "remember Toby" thread is going to be productive, I think we
need to define the question we're trying to answer here. It should be a
question that could have a clear answer. Is it:


   - "What is the best system in practical terms?" This is an unanswerable
   question, without first agreeing on the definition of "best" --- something
   we're not about to resolve.
   - "What systems are clearly better than plurality?" This is an
   improvement over the above, because the bar is so low that, even if our
   definitions of "better" aren't the same, we should be able to find a good
   degree of agreement. However, by the same token, we'll end up with a list of
   systems that's so broad that it makes a worse-than-useless target for
   activism. A normal voter's eyes will glaze over before we're done even
   defining the terms we need in order to start defining the systems.


(Note: If I were answering this second question, I would certainly include a
number of Condorcet systems. I'm not going to spend time making arguments
against those systems, even if I have such arguments, because I don't think
that's helpful. And I ask others to do the same; as much as possible, this
thread should focus on the positive.)


   - "What systems are better than plurality, for any reasonable definition
   of the word 'better'?" I think that this is the question we should be
   focusing on, because we can reasonably expect to agree on an
   acceptably-short list of answers.

That's why I think that Forest's idea of pareto dominance is useful, not
just for when we want to promote a proposal with ordinary voters, but also
in this discussion right here. I can accept that our goals and values are
not exactly the same. While we all share a basic desire to improve
democracy, and would probably agree on the desirability of a number of
criteria considered independently, we won't always agree when it comes to
trading off one desirable trait against another. So if we are looking for a
practical proposal that we can all get behind, it should be one that doesn't
require any trade-offs, one that is strictly better than the current system
in every way. I think that SODA is the answer. (Though I'm keeping an open
mind, and would certainly happily support a number of other systems).

.....

Sorry for the long message; I hope I said enough to make it worth it.

JQ
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