Are Stable Instances Easy?

@article{Bilu2009AreSI,
  title={Are Stable Instances Easy?},
  author={Yonatan Bilu and Nathan Linial},
  journal={Combinatorics, Probability and Computing},
  year={2009},
  volume={21},
  pages={643 - 660}
}
We introduce the notion of a stable instance for a discrete optimization problem, and argue that in many practical situations only sufficiently stable instances are of interest. The question then arises whether stable instances of NP-hard problems are easier to solve, and in particular, whether there exist algorithms that solve in polynomial time all sufficiently stable instances of some NP-hard problem. The paper focuses on the Max-Cut problem, for which we show that this is indeed the case. 

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