[EM] Is autodeterrence bad? (+STAR fails hyperchicken catastrophically)

[Closed Limelike Curves]

I think the EM mailing list made a wrong turn a while back in
misunderstanding "autodeterrence" as a positive attribute of a voting
system, which discourages burial. I'd like to put forth an argument (which
I'm still somewhat hesitant about) that it's a very *bad* property. Given
the chance, political machines are likely to reach out and grab this third
rail as hard as they can, even if it's terrible for their constituents,
because it maximizes their chances of election.

Start with a 2.5-candidate race between Gore, Bush, and a Nazi (who has a
small, but slightly above zero, level of support). Gore doesn't know
whether he or Bush is more popular in a runoff, but he's certain he and
Bush will make it to the runoff with honest voting. However, he realizes he
can use the Nazi as a bludgeon to increase his chances of winning. He tells
his supporters to cast votes as follows:
Gore – 5/5
Bush – 0/5
Nazi – 4/5

Gore's hope is that the Nazi is polarizing enough to defeat Bush for second
place with Gore's support (at which point he's a weak candidate in the
runoff). Risky? Yes. But it's still plausibly strategic if you think Bush
will back down.

But if Bush's faction thinks the same thing, the Nazi ends up winning.

STAR punishes burial by blowing up the country, creating an extremely
high-stakes game of chicken (hyperchicken?). This game has a mixed Nash
equilibrium that involves blowing up the country with some small (but
positive) probability. The issue isn't that burial is incentivized; it's
that it *can* work, but when it fails, it's so strongly *dis*incentivized
that it can be catastrophic.

This can be especially bad since incentives are even stronger for
candidates and campaigns. Campaigns coordinate strategy; voters take cues
from campaigns and political elites (which is why the two major-party
nominees are always the top-2 winners).

The strategy above would be bad for society, and ambiguous for individual
voters (it could elect either Gore or a Nazi). On the other hand, *great* for
Gore's probability of winning, if Gore

Empirically, this kind of turkey-raising happens all the time. Adam Schiff
spent millions trying to boost the Republican in California over Katie
Porter. The DNC keeps intervening in Republican primaries to help nominate
extremists. They keep doing this because they think it's good for their own
personal chances of winning the election, not because they think it's good
for the country overall. And generally, they're right—even though it risks
electing Nazis, it probably helps Democrats win a few more seats.
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