[EM] Looking for a use for Bucklin. Comparison of IRV, AIRV and Approval for small groups needing an easy handcount.

[Michael Ossipoff]

Meeting MMC, but having chicken dilemma, Bucklin and Beatpath would serve
ok for mutual majorities who were completely mutually trusting and
trustworthy.
As for Beatpath, there's little point for it, because there are equally
easily-counted, and more easiy-counted, methods that meet MMC and _don't_
have chicken dilemma.
Bucklin has a better chance of justification, because its handcount is
easier than that of the pairwise-count methods.
I agree with those here who argue that computer-counting can be fully
secure, and we've been discussing that. But some organizations and
temporary small groups who have a collective choice to make might not have
a computer, with coun-software, conveniently available. Of course they
could conduct their voting at the CIVS website, but suppose that, for some
reason that isn't feasible either.
I'm talking about such a small organization or temporary group. I was
agreenig that electing the CW is good for stability, and avoidance of a
displeased majority. But suppose that small group must do handcounting.
Pairwise-count methods are computation-intensive. The idea is to look at
all of the pairwise preferences that you express, so as to take them all
into account, let you vote all of them, for the purpose of finding the best
compromise that you can get, to avoid a dis-satisfied majority. But, by the
nature of its goal, that's computation-intensive.
So, replacing IRV with Condorcet-IRV, Woodall, or Schwartz Woodall might
not be feasible for the small group that I'm talking about. Automatically
looking at every pairwise preference is out. That leaves two possibilities
that I suggest:
1. Just do IRV. You loose the Condorcet efficiency, and IRV can choose from
a MM-preferred set in a way that violates the wishes of some majority,
causing majority dis-satisfaction. But that isn't so bad, if it's for a
good reason, such as the unfeasibility of a pairwise count. If it's a
political poll, such as the current one at CIVS, maybe you'd prfefer CC
compliance, but it isn't essential. The Greens offer IRV in their platform,
and I have no objection to not recognizing every majority, but only the
mutual majorities, as does IRV. And if it's ok for actual (Green scenario)
official public elections, then it's ok for political polls too--unless you
have the specialized purpose of looking for the best that your faction can
get, by finding the CW.
I've said that, for amicable organizations, IRV is probably too
uncompromising, too adversarial. Sure, but if Condorcet-IRV, Woodall, and
Schwartz Woodall aren't feasible, because pairwise counting is too
computation-intensive, the that's reason enough to say "That's ok." After
all, you or your group won't blame yourself or theirselves, because giving
up CC wasn't done by choice.
2. If it isn't feasible to count every one of everyone's pairwise
prefences, to automatically find the CW compromise, then you could just let
people vote the pairwise preferences that are most important to them, the
ones that they feel it's most important for them to vote, either for
strategy or for just supporting what they like. In other words, use
Approval. Approval is the low-cost, count-efficient, and
Condorcet-efficient method. Instead of counting every pairwise preference,
as CC-complying rank methods do, you could just invite people to vote the
pairwise preferences that they choose to. That's an Approval election.
We've talked about the adantages of Score, whose easy, built-in fractional
ratings mitigate strategic misjudgements.
3. A compromise between those two choices would be Approval-IRV (AIRV).
Same as IRV, by my brief definition, but just let people rank as many
candidates as they want at any rank position (but especially 1st place).
For the purpose of my brief definition, it should be said that a candidate
tops a ranking if, uneliminated, s/he is at least one of the candidates at
that ranking's highest rank-level that has uneliminated candidates.
Kevin Venzke pointed out that AIRV doesn't meet FBC. But it still gives
much Approval advantage, giving non-MM voters a way to elect the CW without
favorite-burial.
Its count is about as easy as ordinary iRV, but it's more
Condorcet-efficient. More count-laborious than Approval, but with IRV's MMC
compliance and no chicken dilemma.
I suggest that AIRV would be a great choice for a small group, needing a
relatively easily handcounted method, and wantng IRV's advantages, along
with better Condorcet efficiency, more considerate of non-MM voters, nicer
to majorities that aren't mutual majorities. In other words, not as
adversarial or uncompromising as IRV.
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As I said, Bucklin is strictlly for mutual majorities that are entirely
mutually trusting and trustworthy. if they aren't, then a chicken dilemma
will make Bucklin's MMC compliance quite meaningless.
When I say, "Bucklin" here, I mean "ER-Bucklin". It shouldn't even be
considered other than in the version that meets MMC. That version
incorporates a delay, to achieve that purpose. That's how it was defined at
electowiki, when Iooked. We've discussed it here and at EM before, so
there's no need to repeat that definition.
But if you're going to propose and use a rank method, there's no reason to
use one that has the chicken dilemma. For example, why use Bucklin instead
of AIRV?
I'd suggest that, if you're wlling to have chicken dilemma, then make it
simpler and make the count easier, and just use Approval, or maybe Score.
Mike Ossipoff
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