Inverted Power Rama Distribution with Applications to Life Time Data

Main Article Content

Chrisogonus K. Onyekwere
George A. Osuji
Samuel U. Enogwe


In this paper, we introduced the Inverted Power Rama distribution as an extension of the Inverted Rama distribution. This new distribution is capable of modeling real life data with upside down bathtub shape and heavy tails. Mathematical and statistical characteristics such as the quantile function, mode, moments and moment generating function, entropy measure, stochastic ordering and distribution of order statistics have been derived. Furthermore, reliability measures like survival function, hazard function and odds function have been derived. The method of maximum likelihood was used for estimating the parameters of the distribution. To demonstrate the applicability of the distribution, a numerical example was given. Based on the results, the proposed distribution performed better than the competing distributions.

Rama distribution, inverted Rama distribution, inverted power Rama distribution, life time distribution, order statistics; goodness of fit.

Article Details

How to Cite
Onyekwere, C. K., Osuji, G. A., & Enogwe, S. U. (2020). Inverted Power Rama Distribution with Applications to Life Time Data. Asian Journal of Probability and Statistics, 9(4), 1-21.
Original Research Article


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