Abstract
We study the inapproximability of Vertex Cover and Independent Set on degree-d graphs. We prove that:
Vertex Cover is Unique Games-hard to approximate within a factor 2−(2+od(1))loglogdlogd
. This exactly matches the algorithmic result of Halperin (SICOMP 2002) up to the od(1)
term.
Independent Set is Unique Games-hard to approximate within a factor O(d/log2d)
. This improves the d/logO(1)(d)
Unique Games hardness result of Samorodnitsky and Trevisan (STOC'06). Additionally, our proof does not rely on the construction of a query-efficient PCP.
Vertex Cover is Unique Games-hard to approximate within a factor 2−(2+od(1))loglogdlogd
. This exactly matches the algorithmic result of Halperin (SICOMP 2002) up to the od(1)
term.
Independent Set is Unique Games-hard to approximate within a factor O(d/log2d)
. This improves the d/logO(1)(d)
Unique Games hardness result of Samorodnitsky and Trevisan (STOC'06). Additionally, our proof does not rely on the construction of a query-efficient PCP.
Original language | English |
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Article number | 3 |
Pages (from-to) | 27-43 |
Number of pages | 17 |
Journal | Theory of Computing |
Volume | 7 |
DOIs | |
State | Published - 2011 |