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Optimal Rates for Estimation of Two-Dimensional Totally Positive Distributions

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 نشر من قبل Cheng Mao
 تاريخ النشر 2020
  مجال البحث الاحصاء الرياضي
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We study minimax estimation of two-dimensional totally positive distributions. Such distributions pertain to pairs of strongly positively dependent random variables and appear frequently in statistics and probability. In particular, for distributions with $beta$-Holder smooth densities where $beta in (0, 2)$, we observe polynomially faster minimax rates of estimation when, additionally, the total positivity condition is imposed. Moreover, we demonstrate fast algorithms to compute the proposed estimators and corroborate the theoretical rates of estimation by simulation studies.



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