[EM] proportional constraints - help needed

[Jonathan Lundell]

On 5 Feb 2013, at 10:23 AM, Peter Zbornik <pzbornik at gmail.com> wrote:
> 
>>> Say the "default" proportional ranking method elects women to all five
>>> seats, and thus that we need to modify it in a good way in order to
>>> satisfy the constraints.
>>> 
>>> Now the question is: How should the quoted seats be distributed in
>>> order to insure
>>> i] that the seats are quoted-in fairly proportionally between the
>>> voters (i.e. the same voters do not get both quoted-in seats) and at
>>> the same time
>>> ii] that the proportional ranking method remains fairly proportional?
>> 
>> Define "fairly proportional", please.
> 
> If "fairly proportional" will be defined, then I my question will be
> easy to answer.
> The definition of  "fairly proportional" is at the core of my question.
> I think there is a trade-off between "ranking proportionality" and
> "quota proportionality",
> i.e. you cannnot in all cases maximalize the proprtionality of both
> the ranking and the distribution of the quoted seats at the same time.
> 
> To quote my previous email:
> I.e. we search for
> a) a quota proportionality measure and
> b) a proportional ranking measure and
> c) a rule, which "optimises" both the "quota proportionality" and the
> "proportional ranking proportionality".
> 
> The optimization in c) above, is what I mean by "fairly proportional".

There is, I think, an underlying misconception here, namely that STV order of election can be interpreted as a ranking of level of support. It's not, in the general case.