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Asymptotic normality for eigenvalue statistics of a general sample covariance matrix when $p/n to infty$ and applications

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 نشر من قبل Zeng Li
 تاريخ النشر 2021
  مجال البحث الاحصاء الرياضي
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The asymptotic normality for a large family of eigenvalue statistics of a general sample covariance matrix is derived under the ultra-high dimensional setting, that is, when the dimension to sample size ratio $p/n to infty$. Based on this CLT result, we first adapt the covariance matrix test problem to the new ultra-high dimensional context. Then as a second application, we develop a new test for the separable covariance structure of a matrix-valued white noise. Simulation experiments are conducted for the investigation of finite-sample properties of the general asymptotic normality of eigenvalue statistics, as well as the second test for separable covariance structure of matrix-valued white noise.



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