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

  • Hazhir Homei
  • Saralees Nadarajah


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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