Warren Smith wrote:
>About Scott Ritchie's "feel alike vote same FAVS" criterion >that all members of a feel-alike group should want to vote the same. > >FAVS is falsified by IRV if incomplete information: > either A or B need 5 more votes to surpass the hated C and/or the 50% mark > (but you do not know which) and your group has 10 votes. So split them. > >I am not sure whether FAVS is satisfied by IRV in complete information >scenarios. > I don't know why you are not sure, because I pointed out in my last post that methods like IRV that are vulnerable to Pushover strategy fail this "FAVS" criterion. Suppose these are the known voting intentions: 48: A 27: B>A 25: C>B On these votes, IRV eliminates C and elects B. The 48A supporters can do nothing to elect A if they all vote uniformly (because if they give their first preference to A any second preferences won't be counted and obviously if they all give their first preference to B or C then they will simply elect whichever one it is), but if from 3 to 20 of them change their first preference vote to C then B will be eliminated and elect A. 45: A 03: C>A (or C, or C>B; sincere is A) 27: B>A 25: C>B Apart from just offending mathematical elegance, this vulnerability to Pushover strategy is the reason why I care about methods failing mono-raise. Chris Benham > > ---- election-methods mailing list - see http://electorama.com/em for list info
