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Condorcet method
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==Potential for tactical voting== {{See also|Tactical voting#Condorcet}} Like all voting methods,<ref>Satterthwaite, Mark. "Strategy-proofness and Arrow's conditions: Existence and correspondence theorems for voting procedures and social welfare functions".</ref> Condorcet methods are vulnerable to [[Tactical voting|compromising]]. That is, voters can help avoid the election of a less-preferred candidate by insincerely raising the position of a more-preferred candidate on their ballot. However, Condorcet methods are only vulnerable to compromising when there is a [[Condorcet cycle|majority rule cycle]], or when one can be created.<ref>{{cite news|work=Economics |last1=Green-Armytage |first1=James |title=Why majoritarian election methods should be Condorcet-efficient |s2cid=18348996|s2cid-access=free }}</ref> Condorcet methods are vulnerable to [[Tactical voting|burying]]. In some elections, voters can help a more-preferred candidate by insincerely lowering the position of a less-preferred candidate on their ballot. For example, in an election with three candidates, voters may be able to falsify their second choice to help their preferred candidate win. Example with the [[Schulze method]]: {| class="wikitable" |- !46 voters !44 voters !10 voters |- |1. A |1. B |1. C |- |2. B |2. A |2. B |- |3. C |3. C |3. A |} * B is the sincere Condorcet winner. But since A has the most votes and almost has a majority, with A and B forming a [[mutual majority criterion|mutual majority]] of 90% of the voters, A can win by publicly instructing A voters to bury B with C (see * below), using B-top voters' 2nd choice support to win the election. If B, after hearing the public instructions, reciprocates by burying A with C, C will be elected, and this threat may be enough to keep A from pushing for his tactic. B's other possible recourse would be to attack A's ethics in proposing the tactic and call for all voters to vote sincerely. This is an example of the [[Chicken (game)|chicken dilemma]]. {| class="wikitable" |- !46 voters !44 voters !10 voters |- |1. A |1. B |1. C |- |2. C* |2. A |2. B |- |3. B* |3. C |3. A |} * B beats A by 8 as before, and A beats C by 82 as before, but ''now'' C beats B by 12, forming a [[Smith set]] greater than one. Even the [[Schulze method]] elects A: The path strength of A beats B is the lesser of 82 and 12, so 12. The path strength of B beats A is only 8, which is less than 12, so A wins. B voters are powerless to do anything about the public announcement by A, and C voters just hope B reciprocates, or maybe consider compromise voting for B if they dislike A enough. Supporters of Condorcet methods which exhibit this potential problem could rebut this concern by pointing out that pre-election polls are most necessary with [[plurality voting]], and that voters, armed with ranked choice voting, could lie to pre-election pollsters, making it impossible for Candidate A to know whether or how to bury. It is also nearly impossible to predict ahead of time how many supporters of A would actually follow the instructions, and how many would be alienated by such an obvious attempt to manipulate the system. {| class="wikitable" |- !33 voters !16 voters !16 voters !35 voters |- |1. A |1. B |1. B |1. C |- |2. B |2. A |2. C |2. B |- |3. C |3. C |3. A |3. A |} * In the above example, if C voters bury B with A, A will be elected instead of B. Since C voters prefer B to A, only they would be hurt by attempting the burying. Except for the first example where one candidate has the most votes and has a near majority, the Schulze method is very resistant to burying.
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