Journal of Statistical Theory and Practice

, Volume 11, Issue 4, pp 670–692 | Cite as

Analysis of lifetime model with discrete mass at zero and one

  • K. Muralidharan
  • Bavagosai PratimaEmail author


Inliers (instantaneous or early failures) are natural occurrences of a life test, where some of the items fail immediately or within a short time of the life test due to mechanical failure, inferior quality, or faulty construction of items and components. A similar situation is observed in mortality studies, where the life pattern of newborn babies includes stillbirths (no life), neonatal births (life less than 28 days may be recorded as 1), and babies surviving a month and longer. The inconsistency of such life data is modeled using a nonstandard mixture of distributions, with degeneracy occurring at 0 and 1, and a probability distribution for positive observations. Keeping the underlying distribution as exponential distribution, we model the inliers situation and propose various estimators and characteristics of the model. The model is implemented on mortality data obtained through the NFHS-3 studies.


Asymptotic distribution early failures failure time distribution infant mortality rate inliers instantaneous failures 

AMS Subject Classification

62F10 62P10 62P25 62P30 


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Copyright information

© Grace Scientific Publishing, 20 Middlefield Ct, Greensboro, NC 27455 2017

Authors and Affiliations

  1. 1.Department of Statistics, Faculty of ScienceMaharaja Sayajirao University of BarodaVadodaraIndia

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