Fixed-Parameter and Approximation Algorithms: A New Look

  title={Fixed-Parameter and Approximation Algorithms: A New Look},
  author={Rajesh Hemant Chitnis and Mohammad Taghi Hajiaghayi and Guy Kortsarz},
A Fixed-Parameter Tractable (FPT) ρ-approximation algorithm for a minimization (resp. maximization) parameterized problem P is an FPT algorithm that, given an instance (x, k) ∈ P computes a solution of cost at most k ·ρ(k) (resp. k/ρ(k)) if a solution of cost at most (resp. at least) k exists; otherwise the output can be arbitrary. For well-known intractable problems such as the W[1]-hard Clique and W[2]-hard Set Cover problems, the natural question is whether we can get any FPT-approximation… 
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Almost Polynomial Factor Inapproximability for Parameterized k-Clique
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A minimization (resp., maximization) problem is called fixed parameter (r, t)-hard for two r, t if there does not exist an algorithm that given a problem instance I with optimum value opt and an
A rigorous paradigm for proving Fixed Parameter Inapproximability via gap reductions
For a parameter k, a minimization (resp., maximization) problem is called fixed parameter (r(k), t(k))-hard for two functions r, t if there does not exist an algorithm that given a problem instance I
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  • Mathematics
  • 2013
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  • Dana Moshkovitz, R. Raz
  • Computer Science, Mathematics
    2008 49th Annual IEEE Symposium on Foundations of Computer Science
  • 2008
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