[EM] FW: IRV Challenge - Press Announcement

[Bob Richard]

> So, this is a legal test of PR-STV not IRV?

Minneapolis adopted IRV for all single-winner offices (including the city council elected from single member districts) and STV for two elected commissions with at-large seats. The plaintiff in the suit is arguing that they are both unconstitutional for the same reasons. I don't recall any arguments in the plaintiff's briefs that are said to apply to one and not the other.


-- 

Bob Richard
Marin Ranked Voting
P.O. Box 235
Kentfield, CA 94914-0235
415-256-9393
http://www.marinrankedvoting.org


Raph Frank wrote:
> So, this is a legal test of PR-STV not IRV?
>
> In any case, the two arguments are
>
> - Loss of vote strength due to exhausted ballots
>
> This seems fair enough, would you consider the following a reasonable
> implementation that avoids the issue?
>
> You could exclude the exhausted ballots from consideration for transfer.
>
> If 'Doug' received first choices
>
> 6000: Doug > Meg
> 2000: Doug > Sue
> 5000: Doug
> Total: 13000
> Surplus: 3000
>
> with a quota of 10000
>
> The 4000 ballots which voted for Doug only would remain with Doug.
>
> The 3000 surplus would be transferred in proportion to the 2nd choices
>
> 2000/(6000+2000) * 3000 =  750 to Sue
> 6000/(6000+2000) * 3000 = 2250 to Meg
>
> So the voters would have their votes split:
>
> Doug>Sue ballots:
> Doug: 1250
> Sue: 750
> Total: 2000 (unchanged)
>
> Doug>Meg ballots
> Doug: 3750
> Meg: 2250
> Total: 6000 (unchanged)
>
> Doug only ballots
> Doug: 5000 (unchanged)
>
> Total
> Doug: 10000 (quota)
> Meg: +2250
> Sue: +750
>
> Each ballot has been split into parts, but the sum remained at a single vote.
>
> The could cause problems if Doug received more than a quotas worth of
> "Doug only" ballots.  In this case, he would remain at more than a
> quota worth of votes.  For example,
>
> 11000: Doug
> 1000: Doug>Meg
> 500: Doug>Sue
> Surplus: 2500
>
> I think the fairest solution here would be
>
> Doug: 11000 (still has 1000 surplus)
> Meg: +1000
> Sue: +500
>
> Otherwise, the Doug>Meg and the Doug>Sue voters would effectively get
> more than 1 vote (though technically, they would get negative votes).
> In effect, Doug keeps more than a quota.
>
> It might also be worth recalculating the quota on the fly, but that
> just adds more complexity.
>
> I am not sure what your concern is about transfers occurring first?
>
> The next issue is rounding problems.  This can be solved by using
> rational numbers.  However, if the rounding was to many decimal
> places, like say 10, then it is only a problem in theory.
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