Bayesian Inference for Skew-Normal Mixture Models With Left-Censoring
Document Type
Article
Publication Date
2013
Keywords
Bayesian inference, Censoring, Mixed-effects models, Skew-normal distribution, Tobit model
Digital Object Identifier (DOI)
https://doi.org/10.1080/10543406.2013.813517
Abstract
Assays to measure concentration of antibody after vaccination are often subject to left-censoring due to a lower detection limit (LDL), leading to a high proportion of observations below the detection limit. Not accounting for such left-censoring appropriately can lead to biased parameter estimates. To properly adjust for left-censoring and a high proportion of observations at LDL, this article proposes a mixture model combining a point mass below LDL and a Tobit model with skew-elliptical error distribution. We show that skew-elliptical distributions, where the skew-normal and skew-t are special cases, have great flexibility for simultaneously handling left-censoring, skewness, and heaviness in the tails of a distribution of a response variable with left-censored data. A Bayesian procedure is used to estimate model parameters. Two real data sets from a study of the measles vaccine and an HIV/AIDS study are used to illustrate the proposed models.
Was this content written or created while at USF?
Yes
Citation / Publisher Attribution
Journal of Biopharmaceutical Statistics, v. 23, issue 5, p. 1023-1041
Scholar Commons Citation
Dagne, Getachew A., "Bayesian Inference for Skew-Normal Mixture Models With Left-Censoring" (2013). Epidemiology and Biostatistics Faculty Publications. 44.
https://digitalcommons.usf.edu/epb_facpub/44
