# Unweighted Coalitional Manipulation under the Borda Rule Is NP-Hard

@inproceedings{Betzler2011UnweightedCM, title={Unweighted Coalitional Manipulation under the Borda Rule Is NP-Hard}, author={Nadja Betzler and Rolf Niedermeier and Gerhard J. Woeginger}, booktitle={IJCAI}, year={2011} }

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…

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## 92 Citations

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