Complexity of and Algorithms for Borda Manipulation
@article{Davies2011ComplexityOA,
title={Complexity of and Algorithms for Borda Manipulation},
author={Jessica Davies and George Katsirelos and Nina Narodytska and Toby Walsh},
journal={ArXiv},
year={2011},
volume={abs/1105.5667}
}We prove that it is NP-hard for a coalition of two manipulators to compute how to manipulate the Borda voting rule. This resolves one of the last open problems in the computational complexity of manipulating common voting rules. Because of this NP-hardness, we treat computing a manipulation as an approximation problem where we try to minimize the number of manipulators. Based on ideas from bin packing and multiprocessor scheduling, we propose two new approximation methods to compute…
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