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Approximation thresholds for combinatorial optimization problems

Uriel Feige
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Abstract

An NP-hard combinatorial optimization problem $Π$ is said to have an {\em approximation threshold} if there is some $t$ such that the optimal value of $Π$ can be approximated in polynomial time within a ratio of $t$, and it is NP-hard to approximate it within a ratio better than $t$. We survey some of the known approximation threshold results, and discuss the pattern that emerges from the known results.

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Uriel Feige. 2003-04-28. Approximation thresholds for combinatorial optimization problems. https://arxiv.org/abs/cs/0304039

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