At 12:59 PM 9/23/2008, Kathy Dopp wrote:
Ralph,
Thank you.
Wow. I just realized - What an absolute arithmetic complicated mess or
arbitrarily unfair system this will be whenever the third choice votes
of voters must be transferred in this same split-vote manner.
Actually, this is not the unfair part, and STV is actually quite
fair, until it starts eliminating candidates. And that isn't the
fractional vote part. When a candidate is eliminated, the votes
transfered aren't divided (unless they were previously divided.)
The worst problem, though, with STV is that voters must be able to
rank more than one candidate. Lewis Carroll was aware of the problem
well over a century ago, and developed a simple solution, which
actually fixes STV quite well -- but nobody has ever tried it, as far
as we know. This is what Warren Smith later called Asset Voting.
Basically, Carroll, as I understand it -- I haven't seen the actual
pamphlet -- proposed that if a ballot is exhausted, the remaining
votes (or fractions of a vote) go to the first choice candidate on
that ballot, to be redistributed as the candidate chooses. Both Smith
and Carroll used the metaphor of "property" for this; the votes
become, as it were, the property of the candidate, to "spend" at will
to create winners.
This allows voters who wish to do so to rank only one candidate, but
not see their votes wasted, presumably.
This is really the same problem as with IRV, it merely looms larger
when only one candidate is being elected. (And when that last seat is
being selected, obviously, STV has reduced to IRV for that seat,
hence this is a simple proof that STV must fail monotonicity, since IRV does.
The *real* problem with IRV isn't monotonicity failure, but center
squeeze, precisely the problem that Robert's Rules of Order notes
with its "preferential voting," functionally the same as IRV except
for a majority requirement (which makes it better, by the way -- but
then it doesn't avoid runoffs. *They* didn't call it "Instant Runoff
Voting," that was a political move; plus when IRV replaces real
runoff elections, it changes results in ways that the electorate
probably won't like. In the U.S., real runoffs seem to reverse the
first round result about one-third of the time; when IRV is
implemented -- usually on the argument that it saves money -- this
effect seems to disappear; the plurality winner goes on to win after
vote transfers.
Has anyone described the mathematical formulas for transferring excess
votes above the threshold amounts by using a mathematical system that
accurately reflects all voters rankings or has this only been done by
using the arbitrary unfair (inaccurate) random selection of ballots
method when it comes to using voters' third or lower rankings in these
multi-seat elections?
Yes. I haven't studied this. There is also Reweighted Range Voting
which does something similar.
Random selection, of course, could be manipulated, since one might
get different results from different passes.
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