[EM] Ultimate SPE Agenda Processing: Sink Swap Bubble

[Kevin Venzke]

Hi Forest and Kristofer,

A couple of old responses. I know Forest has continued to post new ideas.

Kristofer wrote:
> This is about chicken resistance in general, no? I suspect there's a 
> more general impossibility result hiding here: that methods that are 
> burial resistant and Condorcet (in the way the Smith-IRV hybrids or 
> Friendly is) have to make uncharitable interpretations of ballots that, 
> if they were honest, would imply a very different candidate should be 
> elected. (I have no proof of this, but it seems a reasonable hunch.)

I don't want to rule this out. Although I'm disputing here that chicken resistance actually
is about burial, maybe there's a way to frame it in that way that would make sense to me.

I have not studied so many Condorcet methods that (purport to) be chicken-resistant. One
would probably want a way to measure the characteristics of the method (beyond simply
whether it satisfies the CD criterion or some CD criterion). We might look to see reduced
truncation incentive. The difficulty here is that WV methods have, at face value, very low
truncation incentive, lower than Schwartz//IRV. You may end up with the conclusion that
chicken-resistant methods outperform only in very specific scenarios, which would not lead
me to think there is a connection to an impossibility result.

I note also that I dispute that it was warranted to define the CD criterion in such a way
that IRV or any Condorcet method would satisfy it. I've speculated that perhaps DSC comes
closest to the spirit of it. But DSC plainly encourages burial. I guess it makes sense: If
you're going to penalize truncation then sometimes actual burial (order reversal) will be
the result.

Forest wrote:
> Our method disappoints the faction X responsible for creating the cycle by
> electing Y, the candidate that the burial or truncation insincerely helped
> (by raising or by truncating below) to create the cycle subverting the
> sincere CW ... namely Z.
> 
> The sincerity check will actually elect Z ... but most electorates will
> think the check is too costly... so they will have to be content to
> disappoint the faction guilty of creating the insincere cycle ... cycle
> prevention for future elections.

Part of what I want to point out is that you cannot only disappoint the faction that
truncated. You will also disappoint the faction that did what they were supposed to do. And
both factions have the ability to decide to vote differently in response to this potential.

This makes it speculative to believe the effect of chicken resistance is less truncation.
It could as easily be that the effect of chicken resistance is more favorite betrayal (or
fewer candidate nominations by the majority). In either event, will there be fewer cycles?
Sure. Will it be because there are only two candidates in the race? Possibly.

>From an advocacy standpoint, I am disturbed at how close CD takes us to IRV's behavior,
given that probably the easiest criticism of IRV is its failure to detect and take into
account pairwise majorities. Whatever magic a CD method can do by ignoring majorities, IRV
is already doing - and IRV has no truncation incentive, so it's probably doing it more
reliably.

This isn't to say I don't think the chicken dilemma is a problem. I don't want someone to
read my position as that I don't care about it. It's just that I think Mike did not give us
a plausible remedy.

Kevin
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