On finding a minimum dominating set in a tournament (Note)
Theoretical Computer Science
Approximating clique is almost NP-complete (preliminary version)
SFCS '91 Proceedings of the 32nd annual symposium on Foundations of computer science
SIAM Journal on Computing
Efficient probabilistically checkable proofs and applications to approximations
STOC '93 Proceedings of the twenty-fifth annual ACM symposium on Theory of computing
Fixed-Parameter Tractability and Completeness I: Basic Results
SIAM Journal on Computing
On the structure of parameterized problems in NP
Information and Computation
ACM SIGACT News
A threshold of ln n for approximating set cover (preliminary version)
STOC '96 Proceedings of the twenty-eighth annual ACM symposium on Theory of computing
Approximation algorithms for NP-hard problems
On the Amount of Nondeterminism and the Power of Verifying
SIAM Journal on Computing
On fixed-parameter tractability and approximability of NP optimization problems
Journal of Computer and System Sciences - special issue on complexity theory
Complexity and Approximation: Combinatorial Optimization Problems and Their Approximability Properties
(poly(log log n), poly(log log n))-Restricted Verifiers are Unlikely to Exist for Languages in NP
MFCS '96 Proceedings of the 21st International Symposium on Mathematical Foundations of Computer Science
On Limited versus Polynomial Nondeterminism
On Limited versus Polynomial Nondeterminism
Clique is hard to approximate within n1-
FOCS '96 Proceedings of the 37th Annual Symposium on Foundations of Computer Science
\beta_k-Complete Problems and Greediness
\'beta_k-Complete Problems and Greediness
Parent assignment is hard for the MDL, AIC, and NML costs
COLT'06 Proceedings of the 19th annual conference on Learning Theory
W-hardness under linear FPT-reductions: structural properties and further applications
COCOON'05 Proceedings of the 11th annual international conference on Computing and Combinatorics
Fixed-parameter approximation: conceptual framework and approximability results
IWPEC'06 Proceedings of the Second international conference on Parameterized and Exact Computation
| Hi-index | 5.23 |
The inapproximability of non-NP-hard optimization problems is investigated. Techniques are given to show that the problems LOG DOMINATING SET and LOG HYPERGRAPH VERTEX COVER cannot be approximated to a constant ratio in polynomial time unless the corresponding NP-hard versions are also approximable in deterministic subexponential time. A direct connection is established between non-NP-hard problems and a PCP characterization of NP. Reductions from the PCP characterization show that LOG CLIQUE is not approximable in polynomial time and MAX SPARSE SAT does not have a FPTAS under the assumption that NP ⊈ DTIME(2O(√ n log n). A number of nontrivial approximation-preserving reductions are also presented, making it possible to extend inapproximability results to more natural non-NP-hard problems such as TOURNAMENT DOMINATING SET and RICH HYPERGRAPH VERTEX COVER.