# 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}
}
• Published 22 June 2010
• Computer Science, Mathematics
• ArXiv
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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