2007/02/11 by Martin J. Wainwright, Wainwright, Martin J. · 7 citations
Computer Science · Engineering · Mathematics · #FOS: Computer and information sciences #FOS: Mathematics #Image and Signal Denoising Methods #Information Theory (cs.IT) #Photoacoustic and Ultrasonic Imaging #Sparse and Compressive Sensing Techniques #Statistics Theory (math.ST) #cs.IT #math.IT #math.ST #stat.TH
paper · pdf · doi:10.48550/arxiv.math/0702301
Appeared as Technical Report 725, Department of Statistics, UC Berkeley January 2007
openalex publication_date 2007/02/11 · arxiv created 2007/02/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The problem of recovering the sparsity pattern of a fixed but unknown vector β^* ∈ \realp based on a set of n noisy observations arises in a variety of settings, including subset selection in regression, graphical model selection, signal denoising, compressive sensing, and constructive approximation. Of interest are conditions on the model dimension p, the sparsity index s (number of non-zero entries in β^*), and the number of observations n that are necessary and/or sufficient to ensure asymptotically perfect recovery of the sparsity pattern. This paper focuses on the information-theoretic limits of sparsity recovery: in particular, for a noisy linear observation model based on measurement vectors drawn from the standard Gaussian ensemble, we derive both a set of sufficient conditions for asymptotically perfect recovery using the optimal decoder, as well as a set of necessary conditions that any decoder, regardless of its computational complexity, must satisfy for perfect recovery. This analysis of optimal decoding limits complements our previous work (ARXIV: math.ST/0605740) on sharp thresholds for sparsity recovery using the Lasso (ℓ1-constrained quadratic programming) with Gaussian measurement ensembles.