# Norms of structured random matrices

**Authors:** Radosław Adamczak, Joscha Prochno, Marta Strzelecka, Michał Strzelecki

PMC · DOI: 10.1007/s00208-023-02599-6 · 2023-04-09

## TL;DR

This paper analyzes the expected size of structured random matrices using mathematical bounds and norms.

## Contribution

The paper provides optimal bounds for the expected norm of structured random matrices under various entry distributions.

## Key findings

- Optimal bounds for the expected norm of structured random matrices are proven up to logarithmic terms.
- Precise order of expected norms is determined in certain cases up to constants.
- Results are derived using operator norms of Hadamard products of the structure matrix.

## Abstract

For \documentclass[12pt]{minimal}
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				\begin{document}$$X_A=(a_{ij}X_{ij})_{i\le m,j\le n}$$\end{document}XA=(aijXij)i≤m,j≤n the corresponding structured random matrix. We study the expected operator norm of \documentclass[12pt]{minimal}
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				\begin{document}$$X_A$$\end{document}XA considered as a random operator between \documentclass[12pt]{minimal}
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				\begin{document}$$\ell _p^n$$\end{document}ℓpn and \documentclass[12pt]{minimal}
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				\begin{document}$$1\le p,q \le \infty $$\end{document}1≤p,q≤∞. We prove optimal bounds up to logarithmic terms when the underlying random matrix X has i.i.d. Gaussian entries, independent mean-zero bounded entries, or independent mean-zero \documentclass[12pt]{minimal}
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				\begin{document}$$\psi _r$$\end{document}ψr (\documentclass[12pt]{minimal}
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				\begin{document}$$r\in (0,2]$$\end{document}r∈(0,2]) entries. In certain cases, we determine the precise order of the expected norm up to constants. Our results are expressed through a sum of operator norms of Hadamard products \documentclass[12pt]{minimal}
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				\begin{document}$$(A\circ A)^T$$\end{document}(A∘A)T.

## Full-text entities

- **Chemicals:** L (MESH:D007930), Choose (-), K (MESH:D011188)

## Figures

1 figure with captions in the complete paper: https://tomesphere.com/paper/PMC11315791/full.md

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Source: https://tomesphere.com/paper/PMC11315791