http://groups.yahoo.com/group/instantrunoff-freewheeling/message/829
Some of the more "interesting" comments by James Salsman
"Because Condorcet voting can more easily be manipulated by strategic voting (i.e., marking whichever of the top-two candidates you do not want to win dead last after people you like even less), Instant Runoff Voting has been shown to produce the Condorcet winner more often in practice than the Condorcet method."
He provides references.
Has anyone read these preferences? Care to chime in?
The first reference claims to prove that manipulating STV is an NP-complete problem. First, even if true, NP-completeness is not an issue when there are only 3 competitive candidates. Second, "manipulation" under STV is frequently desirable, if it helps to bypass an irrelevant alternative or prevents a voter from falling prey to a monotonicity violation. Third, to the extent that STV helps to perpetuate a two-party duopoly, manipulation is not a concern.
In the fourth reference, Salsman is probably referring to a statement by Merrill to the effect that, in the face of strategic voting, Approval Voting is the method most likely to elect a Condorcet candidate, followed by IRV, and then Condorcet & the other methods. The Condorcet method used by Merrill used Borda as a completion method, so it may well have been more manipulable. I don't know whether it is possible to choose a completion method that would reliably punish (or at least not reward) burying strategy, in the event that burying resulted in a cycle. Maybe using an anti-democratic completion method-- such as electing the candidate with the _worst_ Borda score-- would be necessary to effectively punish burying that could result in a cycle.
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