JSM 2012 Home

JSM 2012 Online Program

The views expressed here are those of the individual authors and not necessarily those of the JSM sponsors, their officers, or their staff.

Online Program Home

Abstract Details

Activity Number: 302
Type: Contributed
Date/Time: Tuesday, July 31, 2012 : 8:30 AM to 10:20 AM
Sponsor: Section on Bayesian Statistical Science
Abstract - #305556
Title: Bayesian Regression for Semicontinuous Data with Variable Selection
Author(s): Jinsu Park*+
Companies: KAIST
Address: #1419, Heemang-Hall, KAIST,291 Daehak-Ro, Daejeon, _, 305-701, South Korea
Keywords: Semicontinuous data ; Stochastic Search Variable Selection ; model misspecification bias ; Truncated normal distribution

In biomedical research, semi-continuous data frequently arise. Regression analysis for such semi-continuous outcome variable is challenging because of the inappropriateness of the normal error assumption. One naive approach is to fit a normal regression with log-transformed outcome variable. A two-part model has been developed allowing for more flexibility where two regressions model the binary part and the continuous part of the data separately. Alternatively, a truncated normal regression is applicable, which assumes an underlying latent variable exists and follows a normal regression, and it can be extended to zero-inflated truncated normal model. In this research, we compare 4 different methods for semi-continuous outcome regression in various scenarios via simulation studies and examine how inferences are affected by different model specifications. In all methods, we conduct Bayesian inference and develop MCMC algorithms for posterior sampling where the Stochastic Search Variable Selection (SSVS) structure is incorporated facilitating variable selection. We apply the 4 methods to investigate the relationship between impulsivity and hazardous drinking in young adulthood.

The address information is for the authors that have a + after their name.
Authors who are presenting talks have a * after their name.

Back to the full JSM 2012 program

2012 JSM Online Program Home

For information, contact jsm@amstat.org or phone (888) 231-3473.

If you have questions about the Continuing Education program, please contact the Education Department.