Faster Algorithms for Feedback Arc Set Tournament, Kemeny Rank Aggregation and Betweenness Tournament

@article{Karpinski2010FasterAF,
  title={Faster Algorithms for Feedback Arc Set Tournament, Kemeny Rank Aggregation and Betweenness Tournament},
  author={Marek Karpinski and Warren Schudy},
  journal={ArXiv},
  year={2010},
  volume={abs/1006.4396}
}
We study fixed parameter algorithms for three problems: Kemeny rank aggregation, feedback arc set tournament, and betweenness tournament. For Kemeny rank aggregation we give an algorithm with runtime \(O^*(2^{O(\sqrt{OPT})})\), where n is the number of candidates, \(OPT \le \binom{n}{2}\) is the cost of the optimal ranking, and O *(·) hides polynomial factors. This is a dramatic improvement on the previously best known runtime of O *(2 O(OPT)). For feedback arc set tournament we give an… 

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