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arXiv · 1706.09231

Asymptotic Confidence Regions for High-dimensional Structured Sparsity

Benjamin Stucky·Sara van de Geer
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Abstract

In the setting of high-dimensional linear regression models, we propose two frameworks for constructing pointwise and group confidence sets for penalized estimators which incorporate prior knowledge about the organization of the non-zero coefficients. This is done by desparsifying the estimator as in van de Geer et al. [18] and van de Geer and Stucky [17], then using an appropriate estimator for the precision matrix $Θ$. In order to estimate the precision matrix a corresponding structured matrix norm penalty has to be introduced. After normalization the result is an asymptotic pivot. The asymptotic behavior is studied and simulations are added to study the differences between the two schemes.

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Benjamin Stucky, Sara van de Geer. 2017-06-28. Asymptotic Confidence Regions for High-dimensional Structured Sparsity. https://doi.org/10.1109/tsp.2018.2807399

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