Unweighted Coalitional Manipulation under the Borda Rule Is NP-Hard
نویسندگان
چکیده
The Borda voting rule is a positional scoring rule where, for m candidates, for every vote the first candidate receives m− 1 points, the second m− 2 points and so on. A Borda winner is a candidate with highest total score. It has been a prominent open problem to determine the computational complexity of UNWEIGHTED COALITIONAL MANIPULATION UNDER BORDA: Can one add a certain number of additional votes (called manipulators) to an election such that a distinguished candidate becomes a winner? We settle this open problem by showing NP-hardness even for two manipulators and three input votes. Moreover, we discuss extensions and limitations of this hardness result.
منابع مشابه
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