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Fitting phase--type scale mixtures to heavy--tailed data and distributions

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 نشر من قبل Leonardo Rojas Nandayapa
 تاريخ النشر 2017
  مجال البحث الاحصاء الرياضي
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We consider the fitting of heavy tailed data and distribution with a special attention to distributions with a non--standard shape in the body of the distribution. To this end we consider a dense class of heavy tailed distributions introduced recently, employing an EM algorithm for the the maximum likelihood estimates of its parameters. We present methods for fitting to observed data, histograms, censored data, as well as to theoretical distributions. Numerical examples are provided with simulated data and a benchmark reinsurance dataset. We empirically demonstrate that our model can provide excellent fits to heavy--tailed data/distributions with minimal assumptions

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