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Revision as of 20:52, 28 July 2005 by KVenzke (talk | contribs) (criteria)

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Condorcet//Approval is an election method according to which the Condorcet winner is elected if one exists, otherwise the Approval voting winner is elected. Approval can be designated by a cutoff placed within the ranking by the voter. Alternatively, all explicitly ranked candidates on a ballot could be considered approved.

Burial resistance

Condorcet methods are generally vulnerable to burying strategy. One faction buries a candidate by ranking him insincerely below other candidates. This is an attempt to give this candidate new or stronger pairwise defeats.

When all explicitly ranked candidates are considered approved, Condorcet//Approval makes burying strategy less likely to succeed than in other Condorcet methods. Burying is only effective when it prevents the targeted candidate from being the Condorcet winner. But a faction can't succeed in this task without then being counted as approving the candidate(s) beneath which the targeted candidate was insincerely ranked. This makes it quite likely that burying strategy will backfire, and cause a candidate to be elected who is actually liked less than the targeted candidate.

Favorite Betrayal criterion compliance

Approval voting's satisfaction of the Favorite Betrayal criterion can be preserved in Condorcet//Approval by using the tied at the top rule. This results in the Improved Condorcet Approval method. However, this variant technically isn't Condorcet-compliant.

Satisfied criteria

Condorcet//Approval satisfies Condorcet and always elects a majority favorite, but doesn't satisfy Smith or the Majority criterion for solid coalitions. It satisfies Minimal Defense (and the Strong Defensive Strategy criterion), the Plurality criterion, and monotonicity.

It fails Clone-Winner, Participation, and Later-no-harm.