Uncovered set: Difference between revisions
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==Notes==
The uncovered set can be thought of as requiring its candidates to have a beatpath of at most three candidates to all other candidates. The Smith set requires a beatpath of at most two candidates (i.e. direct pairwise victory), while the Banks set requires a beatpath of at most all candidates.
'''Independence of covered alternatives''' says that if one option (X) wins an election, and a new alternative (Y) is added, X will win the election if Y is not in the [[uncovered set]]. Independence of covered alternatives implies [[Independence of Smith-dominated Alternatives]] (since independence of covered alternatives implies that one can eliminate everyone outside of the uncovered set without changing the winner, and the uncovered set is a subset of the Smith set, therefore eliminating everyone outside of the Smith set also can't change the winner), which further implies [[Smith criterion|Smith]] and thus [[Condorcet criterion|Condorcet]]. If a method is independent of covered alternatives, then the method fails monotonicity if perfect ties can always be broken in favor of a choice W by using ballots ranking W first.
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