Abstract
We study the asymptotic behaviour of the posterior distributions for a one-parameter family of discontinuous densities. It is shown that a suitably centered and normalized posterior converges almost surely to an exponential limit in the total variation norm. Further, asymptotic expansions for the density, distribution function, moments and quantiles of the posterior are also obtained. It is to be noted that, in view of the results of Ghosh et al. (1994, Statistical Decision Theory and Related Topics V, 183-199, Springer, New York) and Ghosal et al. (1995, Ann. Statist., 23, 2145-2152), the nonregular cases considered here are essentially the only ones for which the posterior distributions converge. The results obtained here are also supported by a simulation experiment.
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REFERENCES
Bickel, P. and Yahav, J. (1969). Some contributions to the asymptotic theory of Bayes solutions, Zeit. Wahrscheinlichkeitsth., 11, 257–275.
Chen, C. F. (1985). On asymptotic normality of limiting density functions with Bayesian implications, J. Roy. Statist. Soc. Ser. B, 47, 540–546.
Ghosal, S., Ghosh, J. K. and Samanta, T. (1995). On convergence of posterior distributions, Ann. Statist., 23, 2145–2152.
Ghosh, J. K., Ghosal, S. and Samanta, T. (1994). Stability and convergence of posterior in non-regular problems, Statistical Decision Theory and Related Topics V (eds. S. S. Gupta and J. O. Berger), 183–199, Springer, New York.
Ibragimov, I. A. and Has'minskii, R. Z. (1981). Statistical Estimation: Asymptotic Theory, Springer, New York.
Johnson, R. A. (1970). Asymptotic expansions associated with posterior distributions, Ann. Math. Statist., 41, 851–864.
Le Cam, L. (1953). On some asymptotic properties of maximum likelihood estimates and related Bayes estimates, University of California Publications in Statistics, 1, 277–330.
Wald, A. (1949). Note on the consistency of the maximum likelihood estimate, Ann. Math. Statist., 20, 595–601.
Walker, A. M. (1969). On the asymptotic behaviour of posterior distributions, J. Roy. Statist. Soc. Ser. B, 31, 80–88.
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Ghosal, S., Samanta, T. Asymptotic Expansions of Posterior Distributions in Nonregular Cases. Annals of the Institute of Statistical Mathematics 49, 181–197 (1997). https://doi.org/10.1023/A:1003127108965
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DOI: https://doi.org/10.1023/A:1003127108965