Hallo, > On the current wikipedia page for the Spoiler Effect, > it says: > > A voting system which satisfies the independence of > irrelevant alternatives criterion is immune to the > spoiler effect, > > Now, considering people use the term Spoiler Effect in > the context of Independence of Clones Criterion , this > statement would imply that satisfaction of IIR implies > satisfaction of ICC.
There are two concepts of "spoilers": Arrow's concept of "irrelevant alternatives" and Tideman's concept of "clones". Neither does Arrow's concept of "irrelevant alternatives" imply Tideman's concept of "clones" nor does Tideman's concept of "clones" imply Arrow's concept of "irrelevant alternatives". They are simply two completely different concepts. So instead of asking which concept of "spoilers" is correct, I suggest that the wikipedia page for "Spoiler Effect" should start with the statement that there are two completely different kinds of "spoilers" and then this page should discuss these two kinds of "spoilers" independently from each other. Markus Schulze ---- Election-methods mailing list - see http://electorama.com/em for list info