# [EM] proportional constraints - help needed

Richard Fobes ElectionMethods at VoteFair.org
Thu Feb 14 10:07:48 PST 2013

```On 2/13/2013 4:51 AM, Peter Zbornik wrote:
> 2013/2/9 Richard Fobes<ElectionMethods at votefair.org>:
>> ...
>>> 2013/2/6 Richard Fobes<ElectionMethods at votefair.org>:
>> ...
>> The method consists of running VoteFair _representation_ ranking
>> calculations. ...
>> ...
>> Tentatively the five open-list party positions are assigned to the five
>> candidates who are ranked as most representative -- according to VoteFair
>> _representation_ ranking.
>>
>> These results are proportional.  And they are very resistant to strategic
>> voting.  The details are explained at this web page:
>>
>>      http://www.votefair.org/calculation_details_representation.html
>>
>
> Does VoteFair representation ranking fulfil the criterion, that
> candidate for seat number 2 is elected proportionally to the elected
> candidate at seat 1, ...

Yes.

> ...
and candidate for seat number 3 is elected
> proportionally to the elected candidates at seats 1 and 2, etc....

This brings up an important point that I was already thinking of
bringing up.

There is a difference between proportionality when the number of seats
is known -- which is what STV is designed for -- and proportionality for
an open-party list where the number of seats that will be won by the
party is not known in advance.

In this case (regarding the first three positions), if the first three
candidates were selected so that each represents one-third of the
voters, and the Green party wins only two seats, then only two-thirds of
the voters will be represented.  That is not proportional in the
legislature, even though the first three party-list positions are
allocated to be very proportional.

VoteFair representation ranking chooses for the third position the most
popular person from among the remaining candidates.  This is a fair
approach for the two-seat win, the three-seat win, and the four-seat win.

At about position # 5 there needs to be some additional calculations.
This is what I referred to when I said that VoteFair _negotiation_
ranking has a method that would be useful starting at about position # 5.

Also note that, as Jameson pointed out in a separate post, in order to
ensure full proportionality beyond the first few seats -- say if ten or
more seats might be won -- there has to be some additional information
from the voters in order to select one or two candidates who represent a
small minority.

> ... as in
> the top-down method of Otten?

I did not find any information about the "top-down method of Otten."  If
you send me a link to a place that describes it, then I can answer this

>> If the tentative results already happen to meet the quota for women, then no
>>
>> If there are no women in any of the tentatively assigned five positions,
>> then the two women who are the most popular according to VoteFair
>> _popularity_ ranking are moved into positions # 2 and # 4, and the men are
>> shifted down.
>>
>> When the men who tentatively won are shifted down (to make room for the two
>> women), their order is preserved (which in the above case means the men in
>> seats # 4 and # 5 are completely removed, and the man who was in position #
>> 3 is moved to position # 5, and the man who was in position # 2 is moved
>> into position # 3).

> This does not necesarily lead to proportionality within the five candidates.

Imposing a quota, by necessity, amounts to disturbing carefully balanced
results.

In other words, if the calculated results achieve proportionality, then
imposing a quota will disturb the proportionality of
otherwise-proportional results.

Also this involves the issue mentioned above, namely that getting
proportional results for a specific number of seats makes it difficult
(impossible?) to add to, or remove from, the list and still also get
proportional results for a different number of seats -- without making
adjustments to earlier positions in the list.

I assume that the Green party is not allowed to submit multiple party
lists and specify that "this party list is used if we win one seat, and
this different party list should be used if we win two seats, and here
is yet another party list that should be used if we win three seats, etc."

>> ...
>> Why is the second woman moved into position # 4 instead of position # 5?
>> Because presumably half of the Green-party voters are women, and presumably
>> you want proportional results if your party should win 4 seats.  (If the
>> quotas are met without needing any adjustments, then the second woman might
>> end up in position # 5, and this would be fair because the results imply
>> that quotas are no longer necessary to override other political priorities.)

> Both presumptions are wrong.

In this case the second woman should be moved into position # 5 -- which
is the minimum quota-based requirement -- rather than moving her into
position # 4.