Publications [#257967] of David B. Dunson
search arxiv.org.Papers Published
- Page, GL; Dunson, DB. "Bayesian Local Contamination Models for Multivariate Outliers.." Technometrics : a journal of statistics for the physical, chemical, and engineering sciences 53.2 (May, 2011): 152-162. [doi]
(last updated on 2026/01/14)Abstract:
In studies where data are generated from multiple locations or sources it is common for there to exist observations that are quite unlike the majority. Motivated by the application of establishing a reference value in an inter-laboratory setting when outlying labs are present, we propose a local contamination model that is able to accommodate unusual multivariate realizations in a flexible way. The proposed method models the process level of a hierarchical model using a mixture with a parametric component and a possibly nonparametric contamination. Much of the flexibility in the methodology is achieved by allowing varying random subsets of the elements in the lab-specific mean vectors to be allocated to the contamination component. Computational methods are developed and the methodology is compared to three other possible approaches using a simulation study. We apply the proposed method to a NIST/NOAA sponsored inter-laboratory study which motivated the methodological development.