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Numerically Stable Evaluation of Moments of Random Gram Matrices with Applications

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 نشر من قبل Khalil Elkhalil
 تاريخ النشر 2017
  مجال البحث الهندسة المعلوماتية
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This paper is focuses on the computation of the positive moments of one-side correlated random Gram matrices. Closed-form expressions for the moments can be obtained easily, but numerical evaluation thereof is prone to numerical stability, especially in high-dimensional settings. This letter provides a numerically stable method that efficiently computes the positive moments in closed-form. The developed expressions are more accurate and can lead to higher accuracy levels when fed to moment based-approaches. As an application, we show how the obtained moments can be used to approximate the marginal distribution of the eigenvalues of random Gram matrices.

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