[EM] Three rounds

[Raph Frank]

On Sat, Nov 15, 2008 at 3:45 PM, Kristofer Munsterhjelm
<km-elmet at broadpark.no> wrote:
> I don't think so. Though I haven't investigated this method, I'm thinking
> that since it uses a divisor method (Sainte-Laguë), there would be instances
> where it breaks quota, just like ordinary Sainte-Laguë breaks quota, since
> quota (no candidate or party should need more than a quota worth of votes to
> get a seat, or get a seat with less than a quota's worth) is incompatible
> with the two criteria Sainte-Laguë meets (population pair and house
> monotonicity).

Well, I was thinking if the proposal was used with d'Hondt.

> Perhaps something like "if the method, when electing k winners,
> returns the set X, and there is a way of partitioning the ballots into k
> piles so that each pile has a CW, and each CW is in X, then the method
> passes this criterion".
> Or, is there something that is to the Droop proportionality criterion as the
> Smith criterion is to mutual majority?

In the single winner case, Droop proportionality says that if a
majority ranks a group of candidates above all other candidates, then
one of those candidates will win.  All methods that meet the condorcet
criterion would also meet the Droop proportionality criteron.
However, all single winner methods that meet the Droop proportionality
criterion don't necessarily meet the condorcet criterion.  IRV being
an example that meets the Droop proportionality criterion but not meet
the condorcet criterion.

In that context, a multi-winner condorcet criterion would have to a
stricter requirement than merely meeting the Droop criterion and any
method that fails the Droop proportionality criterion would have to
fail it.