3 research outputs found

    Random polytopes obtained by matrices with heavy tailed entries

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    Let Γ\Gamma be an N×nN\times n random matrix with independent entries and such that in each row entries are i.i.d. Assume also that the entries are symmetric, have unit variances, and satisfy a small ball probabilistic estimate uniformly. We investigate properties of the corresponding random polytope ΓB1N\Gamma^* B_1^N in R\mathbb{R} (the absolute convex hull of rows of Γ\Gamma). In particular, we show that ΓB1Nb1(Bnln(N/n)B2n). \Gamma B_1^N \supset b^{-1} \left( B_{\infty}^n \cap \sqrt{\ln (N/n)}\, B_2^n \right). where bb depends only on parameters in small ball inequality. This extends results of \cite{LPRT} and recent results of \cite{KKR}. This inclusion is equivalent to so-called 1\ell_1-quotient property and plays an important role in compressive sensing (see \cite{KKR} and references therein).Comment: Last version, to appear in Communications in Contemporary Mathematic

    Random polytopes obtained by matrices with heavy tailed entries

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    Let Γ\Gamma be an N×nN\times n random matrix with independent entries and such that in each row entries are i.i.d. Assume also that the entries are symmetric, have unit variances, and satisfy a small ball probabilistic estimate uniformly. We investigate properties of the corresponding random polytope ΓB1N\Gamma^* B_1^N in R\mathbb{R} (the absolute convex hull of rows of Γ\Gamma). In particular, we show that ΓB1Nb1(Bnln(N/n)B2n). \Gamma B_1^N \supset b^{-1} \left( B_{\infty}^n \cap \sqrt{\ln (N/n)}\, B_2^n \right). where bb depends only on parameters in small ball inequality. This extends results of \cite{LPRT} and recent results of \cite{KKR}. This inclusion is equivalent to so-called 1\ell_1-quotient property and plays an important role in compressive sensing (see \cite{KKR} and references therein).Comment: Last version, to appear in Communications in Contemporary Mathematic
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