I never claimed that EQTOP-MPO satisfied any strategy free criteria. To the contrary I pointed out the drawback that it requires approval style strategy even in the zero info case.
That method was just the introduction to a better method that immediately followed it in the same message. Here's the improved version of PG-MPO (for want of a better name): Ballots are range style. For each candidate X and each range level R, let A(X,R) be the number of ballots on which X is rated at level R or above. Let B(X,R) be the greatest number of ballots on which any one candidate is rated above X while X is rated below R (hence PG). In other words, B(X,R) is the max pairwise opposition for X when all ratings above R are collapsed to level R. Let R be the highest range level for which there is a candidate X for which the difference A(X,R)-B(X,R) is positive. Elect the candidate X with the largest such difference at that level R. Since Mike's example did not include ratings, this method cannot be applied to it. Forest Mike O. wrote ... > >Forest-- > >Example with EQTOP - MPO MAMPO: > >1000 voters: > >380: AB >124: B >124: CB >124: DB >124: EB >124: FB > >Its obvious that this example is a failure example for EQTOP-MPO MAMPO with >the votes-only counterparts of SFC and SDSC. But Ill demonstrate that >obvious fact anyway, at the end of this message. > >Note that, in this example, the A voters arent even truncating or using any >kind of offensive strategy. >That suggests that Steve Eppleys name for votes-only SFC >(Truncation-Resistance) isnt general enough. >Likewise, the well-known IRV fails without truncation or any offensive >strategy. > >By the way, it was Steve Eppley who first proposed the votes-only >counterpart to SFC. I didnt like it because (as I discussed yesterday) it >doesnt tell the important guarantee of SFC that I want to tell. Its lack >of applicability to all methods is another reason to not accept is as a >replacement for SFC. > >If people would prefer, Ill use the votes-only counterparts of SFC and >SDSC, when evaluating rank methods (but not when comparing them to nonrank >methods). I do so with the understanding that my preference versions are the >actual criteria, and the votes-only versions are only a convenience, when >comparingrank methods to eachother. > >Ill do that because its true that my preference criteria are a little less >convenient for rank methods. And they require information, preferences, that >neednt be involved when comparing rank methods to each other.. And we all >know that only rank methods are going to pass SFC and SDSC anyway. For that >reason the preference versions could even be called inelegant, when >comparing only rank methods. > >But, when its necessary to evaluate or compare to nonrank methods, the >elegance comparison between votes-only and preference is reversed. Then, the >preference criteria are the ones that are elegant, because of their uniform >applicability to all methods. > >When comparing all methods, theres nothing elegant or convenient about the >votes-only criteria, and their use of FARCS. In fact, votes-only loses its >meaning when FARCS calls intended rankings (which cant even really be >intended) votes. > >Of course heres why the example is a failure example for EQTOP - MPO MAMPO, >with votes-only SFC & SDSC: > >A majority rank B over A, but no majority rank anyone over B. But A wins. > >A majority rank B over A, and dont rank A. But A wins. > >For applying the preference SFC and SDSC, it would be necessary to state >preferences, and to make the rankings of the {B,C,D,E,F} voters complete, to >satisfy the sincerity requirement of SFC. But EQTOP-MPO MAMPO fails >preference SFC and SDSC too. > > >Mike Ossipoff ---- election-methods mailing list - see http://electorama.com/em for list info