Approximating Subdense Instances of Covering Problems
Data Structures and Algorithms
2010-11-10 v2 Discrete Mathematics
Abstract
We study approximability of subdense instances of various covering problems on graphs, defined as instances in which the minimum or average degree is Omega(n/psi(n)) for some function psi(n)=omega(1) of the instance size. We design new approximation algorithms as well as new polynomial time approximation schemes (PTASs) for those problems and establish first approximation hardness results for them. Interestingly, in some cases we were able to prove optimality of the underlying approximation ratios, under usual complexity-theoretic assumptions. Our results for the Vertex Cover problem depend on an improved recursive sampling method which could be of independent interest.
Cite
@article{arxiv.1011.0078,
title = {Approximating Subdense Instances of Covering Problems},
author = {Jean Cardinal and Marek Karpinski and Richard Schmied and Claus Viehmann},
journal= {arXiv preprint arXiv:1011.0078},
year = {2010}
}