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Re:Arrow's impossibility theorem by SilasX on Wednesday June 03, 2015 @08:23PM (#9656755)
Yeah, but that takes the punch out of the theorem. It's saying, "hey, sometimes you have really screwy preferences, too bad."

Realistically, that kind of situation doesn't break a voting system. We can say "we don't care about that case -- just pick a random winner then", but it's no longer deterministic.

Is there a stronger version of the theorem that says there's no sane procedure even ignoring those cases?

Re:Arrow's impossibility theorem by gweinberg on Wednesday June 03, 2015 @10:18PM (#9657075)
No, of course not. It's really easy to come up with a system that always comes up with "good" results if you rule out "screwy" voter preferences, with a sufficiently restrictive value of "screwy".
Re:Arrow's impossibility theorem by SilasX on Wednesday June 03, 2015 @10:28PM (#9657107)
"Screwy" in this context means the sort of intransitive situations referred to in the parent of my last comment.
Re:Arrow's impossibility theorem by reagency on Thursday June 04, 2015 @12:28AM (#9657448)
That is all the punch he theorem has. Arrows theorem shows that aggregate preferences have ties even when individuals don't, and strategic voting can tip the results in those cases.