[EM] Request comments on MMP?

[James Gilmour]

> At 09:26 +0100 5.8.2003, James Gilmour wrote:
> >Different rules can produce different results:
> >d'Hondt favours the larger parties, Sante-Lague favours the smaller 
> >parties, while modified
> >Sante-Lague tries to be neutral

Olli replied: 
> D'Hondt favours large parties, Sainte-Laguë is neutral, modified 
> Sainte-Laguë makes the first seat more difficult, which favours 
> larger parties.

Not according to my calculations, using divisors 1, 2, 3, etc for d'Hondt; 0.5, 1.5, 2.5, etc for
Sainte-Laguë; and 0.7, 1.5, 2.5, etc for modified Sainte-Laguë.  Look at these two elections for
five places with three parties R, S and T.

Election 1: R 520 votes, S 340 votes, T 140 votes.
Seats: d'Hondt R 3, S 2, T 0;  S-L R 2, S 2, T 1;  mod S-L R3, S 2, T 0.

Election 2: R 520 votes, S 330 votes, T 150 votes.
Seats: d'Hondt R 3, S 2, T 0;  S-L R 2, S 2, T 1;  mod S-L R 2, S 2, T 1.

Unless I've made a mistake in my arithmetic, I don't think you can say Sainte-Laguë is neutral.


> If we regard both methods as algorithms to find a suitable quota, 

I don't find this approach at all helpful.  Arithmetically the result is the same, but the problem
with the quota approach to the allocation of seats to parties is "so many quotas each, but what do
we do with the remainders to fill the last seat?"  The advantage of the formula approach is that the
arithmetic is integer (whole seats) and consistent all the way through.

James