That anti-IRV letter mis-represnted IRV in action in Australia, in some places confusing it with corrupted
Hare-Clarke /quasi-list PR that is used to elect the Australian Senate.
As a replacement for Plurality or Top Two Runoff, I consider IRV to be a very worthwhile reform.
I rate all methods that meet (Mutual) Majority and Clone Independence to be at least slightly better than
all methods that do not.
IRV and Plurality have (as Woodall would put it) have different "sets of properties", ie they have different
flaws and comply with different technical criteria. I have seen some plausible-looking anti-IRV propaganda
that rests on some made-up examples. When comparing any two imperfect methods, it alway possible to
contrive some example in which one seems to perform much better than the other.
As Eric Gorr wrote (Fri.Apr.23):
Examples have previously been given which demonstrates IRV inability to perform better then Plurality. In these cases, IRV has failed to select the Condorcet Winner while Plurality did select the Condorcet Winner.So what? It is well-known (and obvious) that IRV is FAR more likely to elect the Condorcet Winner than
Plurality. So if anyone mentions the CW in an informed honest discussion of IRV vs. Plurality, it should be to
chalk up a point for IRV .
To seriously make the case that IRV is not better than Plurality, instead of talking about the made-up example a person
should
(a) make the case that compliance with mostly sundry mathematical neatness criteria (like Participation and Monotoncity)
weigh as much as compliance with (mutual) Majority and Clone Independence.
(b) and/or point to some computer simulations which show something
(c) and/or maybe even point to some real-life examles. IRV has been in use in public political elections for most of a century.
Chris Benham
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