An improved approximation algorithm for ATSP

@article{Traub2020AnIA,
  title={An improved approximation algorithm for ATSP},
  author={Vera Traub and Jens Vygen},
  journal={Proceedings of the 52nd Annual ACM SIGACT Symposium on Theory of Computing},
  year={2020}
}
  • Vera Traub, J. Vygen
  • Published 2 December 2019
  • Computer Science, Mathematics
  • Proceedings of the 52nd Annual ACM SIGACT Symposium on Theory of Computing
We revisit the constant-factor approximation algorithm for the asymmetric traveling salesman problem by Svensson, Tarnawski, and Végh [STOC 2018]. We improve on each part of this algorithm. We avoid the reduction to irreducible instances and thus obtain a simpler and much better reduction to vertebrate pairs. We also show that a slight variant of their algorithm for vertebrate pairs has a much smaller approximation ratio. Overall we improve the approximation ratio from 506 to 22+ε for any ε > 0… 
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