Run IRV as usual eliminating one-by-one the candidates with least first rank support among the remaining candidates UNTIL only the winner survives OR the one on the chopping block is found to dominate every other remaining candidate by the covering relation. If I were an IRV supporter with a firm belief that low first rank support was the best single indicator of inferior support, it might be hard to convince me that a runoff loser should be promoted to election winner solely on the basis that she was unbeaten pairwise among the remaining candidates. But if she Pareto Dominated them or (more generally) pairwise beat not only them but also every candidate beaten by them (i.e. "covered" them), that extreme domination might convince me of her worthiness of the golden buzzer. This rule ensures that a member of the Smith set will be elected, which implies that it is immune from the IRV fiasco of Burlington 2008. Pretty simple: before eliminating a candidate first check to make sure it doesn't cover the the other remaining candidates. FAQ: How to explain that such a strong candidate could be in danger of elimination? Answer: It's due to the well known "squeeze effect" wherein surrounding candidates with less depth of support end up intercepting many of the first place votes, thus garnering enough superficial support to survive early elimination, at the expense of the surrounded candidate. So the cover check is insurance against unmerited squeeze-out. Not convinced? Compare Yee Diagrams before and after the tweak! Sent from my MetroPCS 4G LTE Android Device

On 7/20/21 5:41 AM, Susan Simmons wrote: > Run IRV as usual eliminating one-by-one the candidates with least first > rank support among the remaining candidates UNTIL only the winner > survives OR the one on the chopping block is found to dominate every > other remaining candidate by the covering relation. > > If I were an IRV supporter with a firm belief that low first rank > support was the best single indicator of inferior support, it might be > hard to convince me that a runoff loser should be promoted to election > winner solely on the basis that she was unbeaten pairwise among the > remaining candidates. I've always found FairVote's enthusiasm for "Core Support" to be somewhat disingenuous. If the core support criterion is an absolute requirement, then nobody with zero first preferences should be elected. However, IRV can elect someone with a single first preference if the transfers are right. So zero first preferences is bad but one is good? If core support is the end-all be-all, then surely Plurality must be a better contender. It also clearly fails IIA: augment an election by having the voters vote for themselves in first place and now no candidate has more than a single first preference. If core support is to be taken seriously, it must mean something different from "first preferences". But it shouldn't be a tailor-made criterion that says "whatever IRV does", either. -km