[EM] Ranking of Greeen-scenario methods.

Michael Ossipoff email9648742 at gmail.com
Mon Oct 14 09:12:19 PDT 2013


Merit ranking of methods, for the Green scenario:

1. Woodall
2. Benham
3. AIRV (defined below)
4. IRV
5. Beatpath, RP, Approval, Score

AIRV (Approval-IRV):

Same as IRV, except allows equal ranking (at least for 1st place), and
all the candidates currently sharing top position in a ranking are
regarded as topping that ranking.

[end of AIRV definition]

As for why Woodall and Benham are ranked highest, and why Woodall is
above Benham, it's for reasons stated in my previous post, and others
before that.

AIRV is the next best thing.

Though IRV's failure of the Condorcet Criterion (CC) can make a
strategy situation, sincere voting can still be justified. The chicken
dilemma, to which Beatpath & RP are subject, can't be ignored. When it
exists, strategy is needed. The chicken dilemma is worse than IRV's CC
failure.

Hence Beatpath's and RP's rank-postion below that of IRV.

Approval, Score, Beatpath & RP are ranked equally at the bottom of
that list of methods (but above those not ranked), because FBC, though
not needed in the Green scenario, never really stops being somewhat
desirable. If there were still a favorite-burial incentive for
Beatpath, then Approval would be better than Beatpath. If there were
no chicken dilemma, Beatpath & RP would probably be the very best.
...but chicken dilemma will be common in public political elections.

I once wrote to some Beatpath-using organizations, offering Woodall
and Benham (but especially Schwartz-Woodall), because of freedom from
chicken dilemma.

I was told that their organizations didn't have chicken dilemma.

That's good. If they don't have the chicken dilemma, then
Beatpath/CSSD is probably the best choice for those organizations.
That gives me reason to be glad that I introduced wv Condorcet,
pointed out some advantages of it, and offered Beatpath/CSSD to
organizations.

Comparing Beatpath, SSD, and RP:
------------------------------------------------

Beatpath and CSSD are equivalent.

In public political elections, with many voters and no pairwise ties,
Beatpath, CSSD and SSD are equivalent.

In comparison to Ranked-Pairs (RP), Beatpath is easier to program, and
somewhat faster to compute (though computation time for Beatpath or RP
will be negligible with modern computers).

But RP is incomparably more briefly-defined, and therefore easier to
propose. And its rule-justification is clearer and more obvious.

As a proposal for public elecions, the considerations in the paragraph
before this one are more important. But, for many organizations, the
considerations in the paragraph before that are more important,
explaining why it is Beatpath/CSSD that those organizations use.

A detail: It is said that CSSD stands for Cloneproof SSD. And it now
does, and that's fine. But when I named CSSD, I meant "Committee SSD",
because in small committees, where there can be pairwise-ties, that's
where CSSD and SSD can differ, and where CSSD has an advantage over
SSD.

Anyway, Beatpath/CSSD, SSD, and RP, are disqualified, by the chicken
dilemma, from public political elections, though they're probably the
best for organizations that are sure that they don't have chicken
dilemma.



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