On the NP-Hardness of Approximating Ordering Constraint Satisfaction Problems
Computational Complexity
2013-07-22 v1
Abstract
We show improved NP-hardness of approximating Ordering Constraint Satisfaction Problems (OCSPs). For the two most well-studied OCSPs, Maximum Acyclic Subgraph and Maximum Betweenness, we prove inapproximability of and . An OCSP is said to be approximation resistant if it is hard to approximate better than taking a uniformly random ordering. We prove that the Maximum Non-Betweenness Problem is approximation resistant and that there are width- approximation-resistant OCSPs accepting only a fraction of assignments. These results provide the first examples of approximation-resistant OCSPs subject only to P \NP.
Cite
@article{arxiv.1307.5090,
title = {On the NP-Hardness of Approximating Ordering Constraint Satisfaction Problems},
author = {Per Austrin and Rajsekar Manokaran and Cenny Wenner},
journal= {arXiv preprint arXiv:1307.5090},
year = {2013}
}