[EM] British Colombia considering change to STV

[Raph Frank]

On Sun, May 3, 2009 at 12:13 AM, Anthony O'Neal <watermark0n at gmail.com> wrote:
> It is a rather huge problem.  It effects the proportionately surprisingly
> little though - all the major parties still win a roughly fair number of
> seats.  Districting tends to produce much more proportional results than the
> seat size would suggest, as random political differences in geography give
> some smaller parties too much support in some areas to make up for their
> unfair lack of support in other other areas.

This isn't entirely unreasonable.  If you look at the seat percentage
to first preference vote percentage, it isn't as bad as would be
expected for small parties.  However, even then, the larger parties
get a boost purely due to being larger parties.

However, that doesn't mean that single seaters will give the same
number of parties as a PR system.

Local variation might be able to take a party with 5% support
nationwide up to 15-20% in certain areas, but it isn't going to be
able to take it to 50%.

Single seat districts tend towards a 2 party system with 3rd parties
getting almost no vote.

> This is clear just looking at
> single-member districts.  Event though the threshold is technically 50%,
> it's rather obviously much fairer than a party list system with a 50%
> threshold.  As the number of seats gets larger, this effects seems to be
> exponential.

You mean increased seats per district increases fairness?  I agree.

>
> However, IMHO, the minimum seats per district should be around five, or at
> least the average amount of seats should be five or seven.  The fact that
> Irelands average number of seats has dwindled so dramatically over the years
> makes it clear that the big parties just can't be trusted when it comes to
> proportionality.

Yup.  It is mainly FF as they are mostly in power, but I doubt FG
would consider it a major problem.

I would make the rule an average of 5+ with a minimum of 3.  I think
this would keep abuse low.

> The minimum number of seats in BC-STV is two, the maximum seven.  There's
> really nothing from keeping them from making nearly every district a two or
> three seater.

Ironically, with 2 parties and 3 seat districts, you are almost back
to single seaters.

This assumes each party wins at least 1 per district.

>  Clearly, as the situation in Ireland shows, this is much
> better than single-member districts, but the article should have been
> amended to state that the average number of seats per a district should be
> around five, which would leave room for two-seaters in rural districts but
> keep the big parties from colluding and implementing a seat number to their
> favor.

I agree, there is always going to be some demand for small districts,
but that shouldn't be allowed to derail a reasonable average.