Greedy algorithms and M-term approximation with regard to redundant dictionaries
Journal of Approximation Theory
Approximation of functions over redundant dictionaries using coherence
SODA '03 Proceedings of the fourteenth annual ACM-SIAM symposium on Discrete algorithms
Greed is good: algorithmic results for sparse approximation
IEEE Transactions on Information Theory
Breaking the k2 barrier for explicit RIP matrices
Proceedings of the forty-third annual ACM symposium on Theory of computing
Full length article: On the size of incoherent systems
Journal of Approximation Theory
Full length article: On performance of greedy algorithms
Journal of Approximation Theory
Journal of Approximation Theory
A note on the hardness of sparse approximation
Information Processing Letters
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We study the efficiency of greedy algorithms with regard to redundant dictionaries in Hilbert spaces. We obtain upper estimates for the errors of the Pure Greedy Algorithm and the Orthogonal Greedy Algorithm in terms of the best m-term approximations. We call such estimates the Lebesgue-type inequalities. We prove the Lebesgue-type inequalities for dictionaries with special structure. We assume that the dictionary has a property of mutual incoherence (the coherence parameter of the dictionary is small). We develop a new technique that, in particular, allowed us to get rid of an extra factor m^1^/^2 in the Lebesgue-type inequality for the Orthogonal Greedy Algorithm.