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Dynamic Bivariate Normal Copula

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 نشر من قبل Zuoxiang Peng
 تاريخ النشر 2015
  مجال البحث الاحصاء الرياضي
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Normal copula with a correlation coefficient between $-1$ and $1$ is tail independent and so it severely underestimates extreme probabilities. By letting the correlation coefficient in a normal copula depend on the sample size, Husler and Reiss (1989) showed that the tail can become asymptotically dependent. In this paper, we extend this result by deriving the limit of the normalized maximum of $n$ independent observations, where the $i$-th observation follows from a normal copula with its correlation coefficient being either a parametric or a nonparametric function of $i/n$. Furthermore, both parametric and nonparametric inference for this unknown function are studied, which can be employed to test the condition in Husler and Reiss (1989). A simulation study and real data analysis are presented too.



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