Parameter estimation of the hybrid censored log-normal distribution

The two most common censoring schemes used in life-testing experiments are Type-I and Type-II censoring schemes. The hybrid censoring scheme is mixture of Type-I and Type-II censoring schemes. In this work, we consider the estimation of parameters of log-normal distribution based on hybrid censored data. The parameters are estimated by the maximum likelihood method. It is observed that the maximum likelihood estimates cannot be obtained in a closed form. We obtain the maximum likelihood estimates of the unknown parameters using EM algorithm. We also propose approximate maximum likelihood estimates and these can be used as initial estimates for any iterative procedure. The Fisher information matrix has been obtained and it can be used for constructing asymptotic confidence intervals. The method of obtaining optimum censoring scheme is discussed. One data set is analysed for illustrative purposes.

[1]  Bong-Jin Yum,et al.  Development of r,T hybrid sampling plans for exponential lifetime distributions , 1996 .

[2]  N. Balakrishnan,et al.  Point and interval estimation for Gaussian distribution, based on progressively Type-II censored samples , 2003, IEEE Trans. Reliab..

[3]  N. L. Johnson,et al.  Continuous Univariate Distributions. , 1995 .

[4]  Wen-Tao Huang,et al.  Bayesian Sampling Plans for Exponential Distribution Based on Type I Censoring Data , 2002 .

[5]  Debasis Kundu,et al.  Inference Based on Type-II Hybrid Censored Data From a Weibull Distribution , 2008, IEEE Transactions on Reliability.

[6]  Gordon Johnston,et al.  Statistical Models and Methods for Lifetime Data , 2003, Technometrics.

[7]  Irwin Guttman,et al.  Bayesian analysis of hybrid life tests with exponential failure times , 1987 .

[8]  W. Meeker,et al.  Bayesian life test planning for the Weibull distribution with given shape parameter , 2005 .

[9]  Nader Ebrahimi Prediction intervals for future failures in the exponential distribution under hybrid censoring , 1992 .

[10]  Debasis Kundu,et al.  On hybrid censored Weibull distribution , 2007 .

[11]  R. Dykstra,et al.  A Confidence Interval for an Exponential Parameter from a Hybrid Life Test , 1982 .

[12]  Moti Lal Tiku,et al.  Robust Inference , 1986 .

[13]  G. K. Bhattacharyya,et al.  Exact confidence bounds for an exponential parameter under hybrid censoring , 1987 .

[14]  Lam Yeh,et al.  Bayesian Variable Sampling Plans for the Exponential Distribution with Type I Censoring , 1994 .

[15]  Debasis Kundu,et al.  Hybrid censoring schemes with exponential failure distribution , 1998 .

[16]  B. Epstein Truncated Life Tests in the Exponential Case , 1954 .

[17]  N. Balakrishnan,et al.  Reliability sampling plans for lognormal distribution, based on progressively-censored samples , 2000, IEEE Trans. Reliab..

[18]  Debasis Kundu,et al.  Estimating the Parameters of the Generalized Exponential Distribution in Presence of Hybrid Censoring , 2009 .

[19]  Nader Ebrahimi Estimating the parameters of an exponential distribution from a hybrid life test , 1986 .

[20]  Narayanaswamy Balakrishnan,et al.  Estimation of parameters from progressively censored data using EM algorithm , 2002 .

[21]  S. Chakraborti Large sample tests for equality of medians under unequal right-censoring , 1988 .

[22]  Narayanaswamy Balakrishnan,et al.  Optimal Progressive Censoring Plans for the Weibull Distribution , 2004, Technometrics.

[23]  N. Balakrishnan,et al.  Exact likelihood inference based on Type-I and Type-II hybrid censored samples from the exponential distribution , 2003 .

[24]  D. Rubin,et al.  Maximum likelihood from incomplete data via the EM - algorithm plus discussions on the paper , 1977 .

[25]  Debasis Kundu,et al.  Bayesian Inference and Life Testing Plan for the Weibull Distribution in Presence of Progressive Censoring , 2008, Technometrics.

[26]  Debasis Kundu,et al.  On the comparison of Fisher information of the Weibull and GE distributions , 2006 .