July 2007
We introduce a new truncation approach to extend earlier methods for proving consistency in nonparametric Bayesian regression problems to non-compact state spaces. We illustrate the approach by proving posterior consistency for a nonparametric Poisson regression model. The key step is separating points in the parameter space by constructing hypothesis tests with suitably small error rates; we do this for individual pairs of points using our truncation approach, and then exploit the monotone likelihood-ratio property of the Poisson family to show that the tests have exponentially decaying probabilities of type I and II errors.
Keywords: Bayesian; nonparametric Poisson regression; posterior consistency; stochastic ordering; monotone likelihood ratio.
The manuscript is available PDF (136kb) format.
Cite as:
@TechReport{Pill:Wolp:Clyd:2007,
Author = "Natesh S. Pillai and Robert L. Wolpert and Merlise A. Clyde",
Title = "A Note on Posterior Consistency of Nonparametric {P}oisson
Regression Models",
Year = 2007,
Institution = "Duke University Department of Statistical Science",
Type = "Discussion Paper",
Number = "2007-14",
URL = "http://ftp.stat.duke.edu/WorkingPapers/07-14.html",
}