Sharp Sufficient Conditions on Exact Sparsity Pattern Recovery

Kamiar Rahnama Rad

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arXiv · 0910.0456

Sharp Sufficient Conditions on Exact Sparsity Pattern Recovery

Kamiar Rahnama Rad

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Abstract

Consider the $n$-dimensional vector $y=X\be+\e$, where $\be \in \R^p$ has only $k$ nonzero entries and $\e \in \R^n$ is a Gaussian noise. This can be viewed as a linear system with sparsity constraints, corrupted by noise. We find a non-asymptotic upper bound on the probability that the optimal decoder for $β$ declares a wrong sparsity pattern, given any generic perturbation matrix $X$. In the case when $X$ is randomly drawn from a Gaussian ensemble, we obtain asymptotically sharp sufficient conditions for exact recovery, which agree with the known necessary conditions previously established.

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Kamiar Rahnama Rad. 2009-10-13. Sharp Sufficient Conditions on Exact Sparsity Pattern Recovery. https://arxiv.org/abs/0910.0456

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