Hello List Members, I have a thought on a possibly improved IRV method that I would like to run by the list.
The goal of this method is to eliminate some of the bizarre behavior that IRV can exhibit, particularly the property that lowering a candidate's rank on some ballots can lead to that candidate winning the election. It is also hoped this method would pass the Condorcet criteria, and possibly other criteria that traditional IRV does not pass. I call the method "Sequential Advancement". It is based on IRV, but with a different method of determining which candidate to eliminate. Under this method, the first step would be to determine if there is an IRV winner: Test for Winner: For each ballot, one point is awarded to the highest-ranked candidate. If a ballot has two or more candidates tied for the highest rank, each of these candidates receives an equal fraction of a point. If a ballot has no candidate ranked, no point is awarded. After counting all ballots, if the point total for any candidate is greater than 50% of the total points, that candidate wins the election. Sequential Advancement: If there is no winner, one candidate is eliminated, as follows: The candidate with the largest point total computed above automatically advances to the next round. The point totals are then cleared, and the ballots are recounted, awarding one point to the highest-ranked remaining candidate on each ballot and fractional points in the case of equal highest rank. Again, the candidate with the highest point total advances to the next round. This process of clearing the point totals, counting the ballots and advancing one candidate continues until all candidates but one have advanced to the next round. At that point the last unadvanced candidate is eliminated. Iteration: After eliminating one candidate, the ballots are tested again to see if there is as a winner, this time considering only the highest-ranked candidate who had not been eliminated. If not, the process of eliminating one candidate continues until there is a winner. As an alternative, the IRV test for a winner could be ignored, and instead the elimination process used until only one candidate remains. That candidate is declared the winner. It is not clear if there are any situations in which this would result in a different outcome. This method of elimination would seem to pass the Condorcet criteria, because in order to be eliminated, a candidate would have to lose a pair-wise contest against all remaining candidates. It might also meet the monotonic criteria and be less-susceptible to strategic voting. Has anyone ever seen a proposal or analysis of a method similar to this? Thank you, Allen Pulsifer pulsifer3 /at/ comcast /dot/ net ---- election-methods mailing list - see http://electorama.com/em for list info
