• Media type: E-Article
  • Title: Bayesian Calculus for Gamma Processes with Applications to Semiparametric Intensity Models
  • Contributor: James, Lancelot F.
  • imprint: Indian Statistical Institute, 2003
  • Published in: Sankhyā: The Indian Journal of Statistics (2003-2007)
  • Language: English
  • ISSN: 0972-7671
  • Keywords: Bayesian Calculus
  • Origination:
  • Footnote:
  • Description: <p>Explicit calculus for the posterior distribution of convolution mixtures of weighted gamma processes on Polish spaces are derived. This serves to extend the results of Lo and Weng (1989) to a semiparametric setting on arbitrary spaces. The result of this study is applied to two different types of general semiparametric multiplicative intensity models. One in which a prior is constructed based on q conditionally independent weighted gamma measures given a Euclidean parameter and a second dependent model where different hazard rates are based on a common mixing measure. The latter model seems natural for some types of deconvolution models or regression models. As an example, it is shown how this provides a full (implementable) posterior analysis of the Cox regression model. The results also provide the explicit posterior distribution for the Poisson/Gamma random field model considered by Wolpert and Ickstadt (1998a).</p>