Dear Eric, you wrote (14 Jan 2003): > Would you care to point to the algorithm you used that > would pick B:E as a kept-defeat.
There is no directed path from candidate E to candidate B with a strength of 4 or more. Therefore, when Ranked Pairs is being used and you get to that point where you have to decide whether B > E (of strength 4) has to be locked or skipped, it is clear that B > E has to be locked because locking B > E cannot result in a directed cycle. Tideman's Ranked Pairs method has the property that when candidate X pairwise beats candidate Y with the strength xy and there is no directed path from candidate Y to candidate X with a strength of at least xy then candidate X must be ranked ahead of candidate Y in the final ranking (because locking the pairwise defeat X > Y cannot create a directed cycle). With this simple observation it is possible to exclude in advance a large number of rankings. Markus Schulze ---- For more information about this list (subscribe, unsubscribe, FAQ, etc), please see http://www.eskimo.com/~robla/em
