James Gilmour wrote:
Abd ul-Rahman Lomax > Sent: Wednesday, December 03, 2008 10:52 PM
The tragedy is that IRV is replacing Top Two Runoff, an older
reform that actually works better than IRV.
I have seen statements like this quite a few times, and they puzzle
me. I can see the benefit in TTRO in knowing before voting at the
second stage which two candidates will actually be involved in the
run-off. But what concerns me is the potential chaos in getting to
that stage. The French Presidential election of 2002 is a good
example of the very bad results that can come from the first round of
TTRO. And we have seen similar problems in some of the mayoral
elections in England where the so-called Supplementary Vote is used
in which the voters can mark their first and second preferences but
only the second preferences for the first stage Top-Two candidates
are counted. In such circumstances the outcome from TTRO is very bad
and I should have thought that an IRV election would have given a
much more representative result. Condorcet might be better still,
but that's a different debate.
I'm not Abd, but I think the argument goes like this: in TTR, if a
(usually) third candidate gets enough FPP votes to make it to the second
round, that candidate has a real chance of winning, since the second
round will be focused on those two candidates alone, whereas, on the
other hand, if it's IRV, then IRV's chaos may deprive the candidate of
its rightful victory, and even if it wouldn't, people can only vote for
the third candidate that would become the winner as one of many, not as
one of two.
If that's right, then the Supplementary vote should give significantly
worse results than TTR, simply because people can't discuss and realign
between the first and second rounds.
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