We proposed a new family of lifetime distributions, namely, complementary exponentiated exponential geometric distribution. This new family arises on a latent competing risk scenario, where the lifetime associated with a particular risk is not observable but only the maximum lifetime value among all risks. The properties of the proposed distribution are discussed, including a formal proof of its probability density function and explicit algebraic formulas for its survival and hazard functions, moments, rth moment of the ith order statistic, mean residual lifetime, and modal value. Inference is implemented via a straightforwardly maximum likelihood procedure. The practical importance of the new distribution was demonstrated in three applications where our distribution outperforms several former lifetime distributions, such as the exponential, the exponential-geometric, the Weibull, the modified Weibull, and the generalized exponential-Poisson distribution. 1. Introduction Several new classes of models have been introduced in recent years grounded in the simple exponential distribution. The main idea is to propose lifetime distributions which can accommodate practical applications where the underlying hazard functions are nonconstant, presenting monotone shapes, since the exponential distribution does not provide a reasonable fit in such situations. For instance, we can cite [1], which proposed a variation of the exponential distribution, the exponential geometric (EG) distribution, with decreasing hazard function, [2], which introduced the exponentiated exponential distribution as a generalization of the usual exponential distribution, which can accommodate data with increasing and decreasing hazard functions, [3], which proposed a generalized exponential distribution, which can accommodate data with increasing and decreasing hazard functions, [4], which proposed the exponentiated type distributions extending the Fréchet, gamma, Gumbel, and Weibull distributions, [5], which proposed another modification of the exponential distribution with decreasing hazard function, [6], which generalizes the distribution proposed by [5] by including a power parameter in this distribution, which can accommodate increasing, decreasing, and unimodal hazard functions, [7], which proposed the Poisson-exponential distribution, and [8], which proposed the complementary exponential geometric distribution, which is complementary to the exponential geometric distribution proposed by [1]. The last two proposed distributions accommodate increasing hazard functions. In this paper,
References
[1]
K. Adamidis and S. Loukas, “A lifetime distribution with decreasing failure rate,” Statistics & Probability Letters, vol. 39, no. 1, pp. 35–42, 1998.
[2]
R. D. Gupta and D. Kundu, “Exponentiated exponential family: an alternative to gamma and Weibull distributions,” Biometrical Journal, vol. 43, no. 1, pp. 117–130, 2001.
[3]
R. D. Gupta and D. Kundu, “Generalized exponential distributions,” Australian & New Zealand Journal of Statistics, vol. 41, no. 2, pp. 173–188, 1999.
[4]
S. Nadarajah and S. Kotz, “The exponentiated type distributions,” Acta Applicandae Mathematicae, vol. 92, no. 2, pp. 97–111, 2006.
[5]
C. Ku?, “A new lifetime distribution,” Computational Statistics & Data Analysis, vol. 51, no. 9, pp. 4497–4509, 2007.
[6]
W. Barreto-Souza and F. Cribari-Neto, “A generalization of the exponential-Poisson distribution,” Statistics & Probability Letters, vol. 79, no. 24, pp. 2493–2500, 2009.
[7]
F. Louzada-Neto, V. G. Cancho, and G. D. C. Barriga, “The Poisson-exponential distribution: a Bayesian approach,” Journal of Applied Statistics, vol. 38, no. 6, pp. 1239–1248, 2011.
[8]
F. Louzada, M. Roman, and V. G. Cancho, “The complementary exponential geometric distribution: model, properties, and a comparison with its counterpart,” Computational Statistics & Data Analysis, vol. 55, no. 8, pp. 2516–2524, 2011.
[9]
F. Louzada-Neto, “Poly-hazard regression models for lifetime data,” Biometrics, vol. 55, no. 4, pp. 1121–1125, 1999.
[10]
J. F. Lawless, Statistical Models and Methods for Lifetime Data, Wiley Series in Probability and Statistics, John Wiley & Sons, New York, NY, USA, 2nd edition, 2003.
[11]
M. J. Crowder, A. C. Kimber, R. L. Smith, and T. J. Sweeting, Statistical Analysis of Reliability Data, Chapman & Hall, London, UK, 1991.
[12]
D. R. Cox and D. Oakes, Analysis of Survival Data, Monographs on Statistics and Applied Probability, Chapman & Hall, London, UK, 1984.
[13]
I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series, and Products, Elsevier, New York, NY, USA, 7th edition, 2007.
[14]
H. M. Barakat and Y. H. Abdelkader, “Computing the moments of order statistics from nonidentical random variables,” Statistical Methods & Applications, vol. 13, no. 1, pp. 15–26, 2004.
[15]
A. Rényi, “On measures of entropy and information,” in Proceedings of the Fourth Berkeley Symposium on Mathematical Statistics and Probability, vol. 1 of Contributions to the Theory of Statistics, pp. 547–561, University of California Press, Berkeley, Calif, USA, 1961.
[16]
R Development Core Team, R Foundation for Statistical Computing, Vienna, Austria, 2010, http://www.R-project.org.
[17]
W. Barreto-Souza, A. L. de Morais, and G. M. Cordeiro, “The weibull-geometric distribution,” Journal of Statistical Computation and Simulation, vol. 81, no. 5, pp. 645–657, 2011.
[18]
K. Adamidis, T. Dimitrakopoulou, and S. Loukas, “On an extension of the exponential-geometric distribution,” Statistics & Probability Letters, vol. 73, no. 3, pp. 259–269, 2005.
[19]
G. S. Mudholkar and D. K. Srivasta, “Exponentiated weibull family: a reanalysis of the bus-motor-failure data,” Technometrics, vol. 37, no. 4, pp. 436–445, 1995.
[20]
G. S. C. Perdoná and F. Louzada-Neto, “A general hazard model for lifetime data in the presence of cure rate,” Journal of Applied Statistics, vol. 38, no. 7, pp. 1395–1405, 2011.
[21]
D. Davis, “An analysis of some failure data,” Journal of the American Statistical Association, vol. 47, no. 258, pp. 113–150, 1952.
[22]
D. G. Hoel, “A representation of mortality data by competing risks,” Biometrics, vol. 28, no. 2, pp. 475–488, 1972.
[23]
M. V. Aarset, “How to identify a bathtub hazard rate,” IEEE Transactions on Reliability, vol. R-36, no. 1, pp. 106–108, 1987.
[24]
Z. W. Birnbaum and S. C. Saunders, “A new family of life distributions,” Journal of Applied Probability, vol. 6, pp. 319–327, 1969.