Partition-Based Priors and Multiple Event Censoring: An Analysis of Rosen's Fibrous Composite Experiment

• Activity Number: 291
• Type: Contributed
• Date/Time: Tuesday, July 31, 2012 : 8:30 AM to 10:20 AM
• Sponsor: Section on Physical and Engineering Sciences
• Author(s): John Grego*+
• Companies: University of South Carolina
• Keywords: load-sharing systems ; non-parametric priors ; Bayes ; Dirichlet processes

Abstract

Multiple event censoring occurs when the censoring mechanism depends on preceding observations. This arises naturally in load sharing systems when component failure under increased load can initiate a series of component failures due to load transfer from the failed components, causing the subsequent component strengths to be interval censored. Here the intervals are determined by the breaking stress that initiates the series of failures. A class of nonparametric priors which are natural conjugate priors for this situation are the partitioned based nonparametric priors recently developed by Sethuraman and Hollander (2009).

Load-sharing systems are used to model fibrous composite materials. The modeling approach is based on some remarkable experiments conducted by Rosen (1964, 1965), who discovered that load could not be transferred through the composite matrix material around a fiber break beyond a distance referred to as the ineffective length. The ineffective length is used to discretize the composite into a system of components for which the load-sharing is determined by mechanical considerations. A Bayesian analysis of the components' strength distribution of the data