A model-based approach for imputing censored data in source apportionment studies.

ABSTRACT: Sources of particulate matter (PM) air pollution are generally inferred from PM chemical constituent concentrations using source apportionment models. Concentrations of PM constituents are often censored below minimum detection limits (MDL) and most source apportionment models cannot handle these censored data. Frequently, censored data are first substituted by a constant proportion of the MDL or are removed to create a truncated dataset before sources are estimated. When estimating the complete data distribution, these commonly applied methods to adjust censored data perform poorly compared with model-based imputation methods. Model-based imputation has not been used in source apportionment and may lead to better source estimation. However if the censored chemical constituents are not imp

SUBMITTER: Krall JR 

PROVIDER: S-EPMC4667983 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature