Steve Eppley wrote (26 Nov 2009): "Can it be said that Later No Harm (LNH) is satisfied by the variation of IRV that allows candidates to withdraw from contention after the votes are cast?"
No. Take this classic (on EM) scenario: 49: A 24: B 27: C>B A is the normal IRV winner, but in the variation you describe C presumably withdraws causing B to win. 49: A 24: B>C 27: C>B If the B supporters instead of truncating vote B>C then C wins. Assuming C accepts the win the B voters have caused B to lose by not truncating, a clear failure of Later-no-Harm. Steve wrote: "Since IRV is said to satisfy LNH, then one must say Plurality Rule satisfies LNH too, because Plurality Rule can be viewed as just a variation of IRV with a smaller limit (one candidate per voter)." Yes, and I did. I listed FPP ("First-Preference Plurality" or more traditionally "First Past the Post") as a method that meets Later-no-Harm. I understand that in the US the Alternative Vote is called IRV, but that sometimes various inferior approximations are given the same label. Chris Benham __________________________________________________________________________________ Win 1 of 4 Sony home entertainment packs thanks to Yahoo!7. Enter now: http://au.docs.yahoo.com/homepageset/ ---- Election-Methods mailing list - see http://electorama.com/em for list info