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A Discrete Gamma Lifetime Model and Its Reliability Applications

Pramendra Singh Pundir, Hare Krishna


In this paper, we have first developed discrete gamma failure (dGam) lifetime model by discretizing the well-known gamma failure distribution. Thereafter, we have given a description of the distributional properties and reliability characteristics of dGam model. The next section consists of a few theorems on dGam and provides a basis for ML and Bayes estimation procedures are carried out in next sections along with a thorough simulation study depicting the behavior of these estimators. Finally, some real life situations have been discussed where dGam provides most plausible fitting.


Gamma distribution, discrete lifetime models, reliability, failure rate

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