[EM] British Colombia considering change to STV

[Raph Frank]

On Sat, May 2, 2009 at 11:33 PM, Juho Laatu <juho4880 at yahoo.co.uk> wrote:
> It practice that seems to set the limits
> to max 4 and min 2 parties/groupings per
> constituency represented in the Dail.
> <http://en.wikipedia.org/wiki/Members_of_the_30th_D%C3%A1il>\

The small constituency sizes do hurt the smaller parties.  This is one
of the big issues I would have.

>> Party list systems aren't neutral at all.
>
> Yes. Or one could say that they may
> allow votes to individuals but they do
> not allow voters to define any arbitrary
> inheritance order of the vote (unlike in
> STV).

Well, the assume that the party is primary.  The inheritance ordering
is decided by the party rather than the voter.

The tree system is a possible compromise as it allows the candidates
some say in what branch of the tree they are in.  At least that the
candidate will be closer to the voter than the party leadership.

I think a candidate list system is better though as it allows more
general inheritance ordering.  Ofc, it is always going to be a
tradeoff between precision and complexity (both for the count and for
the voter).

Closed party list
Open party list
Tree based lists
Candidate list
PR-STV

All, except PR-STV could be handled at the national level.

Party list would allow a much smaller ballot.

The 3 middle options would use the same "pick one candidate" ballot.

> Yes. One could try to limit the number of
> candidates to keep voting easy from the
> voter point of view and to keep the size
> of the ballots sheets manageable.

I think a reasonable compromise here would be to allow candidates to
register as official write-in candidates.  They could be given a code,
and included on a list in the polling station.

In most cases, all of them combined wouldn't achieve enough votes to
get a seat and they could be eliminated as a bloc.

> And of
> course to keep the "irrelevant" candidates
> out
<snip>
> Also money has been used somewhere.

In Ireland, you have to pay a deposit to be on the ballot, if you
don't get at least 25% (I think) of a quota, you lose your deposit.

> ... the parties may benefit of naming numerous
> candidates while in STV nomination of
> numerous candidates might mean that the
> party will have weaker chances of getting
> maximum number of their candidates elected.

This is due to the fact that voters tend not to fill out their ballot fully.

Also, candidate based voters will vote first choice for a popular
local and then vote 2nd choice for another party.

Running fewer candidates can help to lock down the vote for the party.

Basically, surplus/elimination transfers don't ever 100% go to the same party.

> I don't know what is a typical number of
> candidates in one constituency in the
> Irish Dail elections.

It is around 10 - 20.

> In Finnish open
> list elections I'm used to have some 150
> candidates.

OTOH, you only have to pick one of them, rather than provide a ranking
for say 10 of them.

> One problem is that
> the system is not proportional within
> parties since within each party and
> district the system elects simply those
> candidates with most votes.)

Right, the open list system is PR at the party level and then
multi-seat plurality for candidate selection internally.

Maybe they use use Asset Voting for internal party transfers, or maybe
just allow the party to decide on internal rules.

>> Right, but there are surplus transfer issues.
>
> Are there some specific independent candidate
> related surplus transfer issues

I meant with party list systems.

An independent can be expected to get around 1 seat's worth of a vote
(or he should be forming a party).

If I vote for him and he doesn't get elected, I have thrown my vote away.

Similarly, if I vote for him and he gets elected with 1.5 seats worth,
then my vote is only worth 0.67 of a vote.

OTOH, if I vote for a party which gets many votes, then my vote will
have a weight of pretty close to 1.

This also applies with threshold based party list systems.  If I vote
for a party which gets 4.9% of the vote in a system with a 5%
threshold, then I am throwing my vote away.

This creates a disincentive to vote for parties that are close to the
threshold.

In the extreme case, you could have 19 parties with 4.9% of the vote
and 1 party with 6.9% of the vote, and the 6.9% party gets all the
seats in the legislature.

To fix this, at minimum, wasted votes should be reassigned.  I would
also allow surplus transfers for independents (maybe including a rule
that such transfers have to go to parties).

> Could you tell a bit more about the
> intended technique?

Each voter can rank 2 parties.
A party which runs only 1 candidates is considered an independent candidate.

I might vote something like:
1) Independent
2) Party X

The idea would be to pick a party for your 2nd rank that you are
reasonably sure will get a few seats.

1) Count all the first choices
2) Assign seats using d'Hondt
3) Any party or independent that doesn't get a seat is eliminated
4) Any independent who gets a seat has his surplus transferred
(assuming the 2nd choice wasn't eliminated)
5) Assign remaining seats between the parties using Sainte-Laguë, but
all get at least 1 seat

As long as each voter votes for a party that will easily meet the
threshold as their 2nd choice, then everyone is fully represented.

The surplus transfer step is perhaps an unnecessary complexity as it
requires reweighting, but I think the elimination transfers are
important.

> Yes, I agree. In addition to providing
> more exact proportionality I find also
> the property that the voters can steer
> the internal evolution of the party
> interesting.

Candidate list and PR-STV also somewhat allow that, but they are less
transparent.

Also, candidates might form the tree based on geography rather than
ideology.  Ofc, that would depend on what issues the voters think are
important.

I am not sure if wings would be willing to name themselves.

> It is also possible to develop systems
> that mix both styles. That could mean
> e.g. default inheritance order (tree or
> even candidate specific) for short
> (exhausted) votes but allowing voters to
> define their own order / deviate from
> the default order if they so wish.

I agree with that.

In Australia, they have the 'above-the-line' system.  It is PR-STV,
but you must either vote for all the candidates (and there can be
100+) or just pick a party's list.

A better plan would be to allow the voters to pick a party's list and
but if they also rank some candidates, then that overrides the list.

> How exactly did you assume the STV and
> tree/list inheritance (and national level
> proportionality?) to be combined here?

I didn't mean combine them at all.   The only connection would be that
they are held on the same day.

There would be a national list PR election to fill half of the seats
and then the other half would be returned from 5+ seater local
constituencies.

I am not a big fan of MMP like methods that can be abused (as seen in
Italy) or require that a vote for a candidate is assumed to be a vote
for his party (the standard fix for the abuse).