On Products and Mixed Sums of Gamma and Beta Random Variables Motivated by Availability



Motivated by the notion of availability, the exact distribution of the sum of beta random variables is derived under the impact of the environment. A suitable approximation is presented when the exact distribution cannot be identified. Also presented are some characterizations for the gamma distribution.


Availability Beta distribution Lifetime 

Mathematics Subject Classification (2010)



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© Springer Science+Business Media, LLC 2017

Authors and Affiliations

  1. 1.Department of StatisticsUniversity of TabrizTabrizIran
  2. 2.School of MathematicsUniversity of ManchesterManchesterUK

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