[EM] STV - the transferrable part is OK (fair), the sequential round elimination is not

[Raph Frank]

On Tue, Nov 3, 2009 at 4:53 PM, Kristofer Munsterhjelm
<km-elmet at broadpark.no> wrote:
>> The effect is that it is harder for parties to get their first seat.
>> Parties with 2 or more seats are no affected.
>
> Is that true? Consider a maximally unfair variant, something like
> 2.999, 3, 5, 7, 9...
>
> Now the larger parties can get many seats before the intermediate and small
> parties get in the running. This naturally decreases the number of free
> seats that may be allocated to the small parties.

A party which was going to get 2 seats would still get 2 seats.

In fact, it makes it easier for them.

It is like as if the smaller parties don't get any seats, and thus
there are more available for the parties which can get 2+ seats.

The parties which lose out would be the ones who would have originally
obtained only 1 seat.

> STV has an advantage in that it doesn't need to care about parties. I'd
> prefer to preserve that in any competing method.

Well, I was just thinking out loud.  I agree that this is one of the
main benefits of PR-STV.

>> Also, if the districts are only 5 or so seats in size, then it doesn't
>> really help that much at all, as only large parties will get more than
>> 1 seat anyway, though it could help medium parties get a 2nd seat.
>
> Yes. If complexity is not a problem, Schulze's MMP proposal could be used to
> fix that. Norway has something like "party list MMP": a certain number of
> seats are top-up and allocated to maximize proportionality after the
> district seats are allocated, with proportionality presumably being defined
> according to a national Modified Sainte-Laguë count.

Yeah, that is probably an easier method.  However, I like my earlier
proposal better.

I don't agree with the principle of deciding party support based on
first preference votes.