[EM] Sims - method terminology

[Jameson Quinn]

Thanks for the source code. Since I think that my method is almost the same
as Q-range (except in uncommon cases when my method fails to remove a full
Droop quota, and yours I think removes linearly more than mine per voter),
I'm not going to dive in right now. However:

>I'd thought of this method, and consider it a very good one if you're
> willing to go with a non-?>summable, computationally-complex method. I am
> surprised to hear you say that "sincerely voting >this isn't very
> realistic". True, it is not LNH, so truncation is possible; but I don't see
> truncation as >a dominant strategy here....
>


> I believe you will have a perfectly typical truncation dilemma when your
> side has two near-clones and you expect a candidate on the other side to
> be the initial leader.
>

No. If voters are using purely rational strategy, and they know which
near-clone is likely to be the first-round frontrunner, the voters for that
candidate have no motivation to truncate. The second clone's voters will
lower their threshold first. If that's not enough for the first clone to
win, because of truncation, then the first clone is out of the running (if
they can't expect other-side crossover votes) or a lock-in (if they can).
The only thing that first-clone truncation can accomplish is to elect the
other-side candidate.

So the rational strategic result is for the second clone to win, or the
more-centrist one if there are enough crossover votes. This is, in some
cases, not the best result; however, the crucial point is that eliminates
the race-to-the-bottom dynamic from truncation. I believe that humans will
not behave as rational selfish utility-maximizers in this case; that without
the race-to-the-bottom, insincere truncation (that is, truncation of a
nearly-equal-utility candidate, which could not be "honestly" motivated by a
zero-information-strategy among the plausible frontrunners) will be rare.

>
>
> By the way, it has occurred to me that I can attempt to determine what
> is a "realistic" set of candidate placements by excluding scenarios that
> are not competitive. Unfortunately I'm not producing this data yet.
>

There's plenty of real-world elections which aren't very competitive. Or am
I not understanding what you're saying? Do you mean "useful for
discriminating between methods" instead of "realistic"?

JQ
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