An important issue in survival analysis is the investigation and the modeling of hazard rates. Within a Bayesian nonparametric framework, a natural and popular approach is to model hazard rates as kernel mixtures with respect to a completely random measure. In this paper we provide a comprehensive analysis of the asymptotic behavior of such models. We investigate consistency of the posterior distribution and derive fixed sample size central limit theorems for both linear and quadratic functionals of the posterior hazard rate. The general results are then specialized to various specific kernels and mixing measures yielding consistency under minimal conditions and neat central limit theorems for the distribution of functionals.
References
[1] Barron, A., Schervish, M. J. and Wasserman, L. (1999). The consistency of distributions in nonparametric problems. Ann. Statist. 27 536–561.
[2] Brix, A. (1999). Generalized gamma measures and shot-noise Cox processes. Adv. in Appl. Prob. 31 929–953.
[3] Daley, D. and Vere-Jones, D. J. (1988). An Introduction to the Theory of Point Processes. Springer, New York.
Mathematical Reviews (MathSciNet):
MR950166
[4] Doksum, K. (1974). Tailfree and neutral random probabilities and their posterior distributions. Ann. Probab. 2 183–201.
Mathematical Reviews (MathSciNet):
MR373081
[5] Drăghici, L. and Ramamoorthi, R. V. (2003). Consistency of Dykstra-Laud priors. Sankhyā 65 464–481.
[6] Dykstra, R. L. and Laud, P. (1981). A Bayesian nonparametric approach to reliability. Ann. Statist. 9 356–367.
Mathematical Reviews (MathSciNet):
MR606619
[7] Feller, W. (1971). An Introduction to Probability Theory and Its Applications. Vol. II, 3rd ed. Wiley, New York.
Mathematical Reviews (MathSciNet):
MR270403
[8] Ghosal, S., Ghosh, J. K. and Ramamoorthi, R. V. (1999). Posterior consistency of Dirichlet mixtures in density estimation. Ann. Statist. 27 143–158.
[9] Ghosh, J. K. and Ramamoorthi, R. V. (1995). Consistency of Bayesian inference for survival analysis with or without censoring. In Analysis of Censored Data (Pune, 1994/1995). IMS Lecture Notes Monogr. Ser. 27 95–103. IMS, Hayward, CA.
[10] Ghosh, J. K. and Ramamoorthi, R. V. (2003). Bayesian Nonparametrics. Springer, New York.
[11] Hjort, N. L. (1990). Nonparametric Bayes estimators based on beta processes in models for life history data. Ann. Statist. 18 1259–1294.
[12] Ho, M.-W. (2006). A Bayes method for a monotone hazard rate via S-paths. Ann. Statist. 34 820–836.
[13] Ishwaran, H. and James, L. F. (2004). Computational methods for multiplicative intensity models using weighted gamma processes: Proportional hazards, marked point processes, and panel count data. J. Amer. Statist. Assoc. 99 175–190.
[14] James, L. F. (2003). Bayesian calculus for gamma processes with applications to semiparametric intensity models. Sankhyā 65 179–206.
[15] James, L. F. (2005). Bayesian Poisson process partition calculus with an application to Bayesian Lévy moving averages. Ann. Statist. 33 1771–1799.
[16] Kabanov, Y. (1975). On extendend stochastic integrals. Teor. Verojatnost. i Primenen. 20 725–737.
Mathematical Reviews (MathSciNet):
MR397877
[17] Kallenberg, O. (1986). Random Measures, 4th ed. Akademie-Verlag, Berlin.
Mathematical Reviews (MathSciNet):
MR854102
[18] Kim, Y. (1999). Nonparametric Bayesian estimators for counting processes. Ann. Statist. 27 562–588.
[19] Kim, Y. (2003). On the posterior consistency of mixtures of Dirichlet process priors with censored data. Scand. J. Statist. 30 535–547.
[20] Kim, Y. and Lee, J. (2001). On posterior consistency of survival models. Ann. Statist. 29 666–686.
[21] Kingman, J. F. C. (1967). Completely random measures. Pacific J. Math. 21 59–78.
Mathematical Reviews (MathSciNet):
MR210185
[22] Kingman, J. F. C. (1993). Poisson Processes. Oxford Studies in Probability 3. Clarendon Press, New York.
[23] Lijoi, A., Prünster, I. and Walker, S. G. (2008). Posterior analysis for some classes of nonparametric models. J. Nonparametr. Stat. 20 447–457.
[24] Lo, A. Y. and Weng, C.-S. (1989). On a class of Bayesian nonparametric estimates. II. Hazard rate estimates. Ann. Inst. Statist. Math. 41 227–245.
[25] Nieto-Barajas, L. E. and Walker, S. G. (2004). Bayesian nonparametric survival analysis via Lévy driven Markov processes. Statist. Sinica 14 1127–1146.
[26] Nieto-Barajas, L. E. and Walker, S. G. (2005). A semi-parametric Bayesian analysis of survival data based on Lévy-driven processes. Lifetime Data Anal. 11 529–543.
[27] Peccati, G. and Prünster, I. (2008). Linear and quadratic functionals of random hazard rates: An asymptotic analysis. Ann. Appl. Probab. 18 1910–1943.
[28] Peccati, G. and Taqqu, M. S. (2008). Central limit theorems for double Poisson integrals. Bernoulli 14 791–821.
[29] Peterson, A.V. (1977). Expressing the Kaplan–Meier estimator as a function of empirical subsurvival functions. J. Amer. Statist. Assoc. 72 854–858.
Mathematical Reviews (MathSciNet):
MR471165
[30] Regazzini, E., Lijoi, A. and Prünster, I. (2003). Distributional results for means of random measures with independent increments. Ann. Statist. 31 560–585.
[31] Rota, G.-C. and Wallstrom, C. (1997). Stochastic integrals: A combinatorial approach. Ann. Probab. 25 1257–1283.
[32] Sato, K. (1999). Lévy Processes and Infinitely Divisible Distributions. Cambridge Studies in Advanced Mathematics 68. Cambridge Univ. Press, Cambridge.
[33] Schwarz, L. (1965). On Bayes procedures. Z. Wahrsch. Verw. Gebiete 4 10–26.
Mathematical Reviews (MathSciNet):
MR184378
[34] Surgailis, D. (1984). On multiple Poisson integrals and associated Markov semigroups. Probab. Math. Statist. 3 217–239.
Mathematical Reviews (MathSciNet):
MR764148
[35] Walker, S. G. (2003). On sufficient conditions for Bayesian consistency. Biometrika 90 482–488.
[36] Walker, S. G. (2004). New approaches to Bayesian consistency. Ann. Statist. 32 2028–2043.
[37] Wu, Y. and Ghosal, S. (2008). Kullback Leibler property of kernel mixture priors in Bayesian density estimation. Electron. J. Stat. 2 298–331.