Addressing extrema and censoring in pollutant and exposure data using mixture of normal distributions.

ABSTRACT: Volatile organic compounds (VOC), which include many hazardous chemicals, have been used extensively in personal, commercial and industrial products. Due to the variation in source emissions, differences in the settings and environmental conditions where exposures occur, and measurement issues, distributions of VOC concentrations can have multiple modes, heavy tails, and significant portions of data below the method detection limit (MDL). These issues challenge standard parametric distribution models needed to estimate the exposures, even after log-transformation of the data. This paper considers mixture of distributions that can be directly applied to concentration and exposure data. Two types of mixture distributions are considered: the traditional finite mixture of normal distributions,

SUBMITTER: Li S 

PROVIDER: S-EPMC3857711 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature