Abstract
Understanding the effect of human-induced pollution on the environment is an important precursor to promoting public health and environmental stability. One aspect of understanding pollution is understanding pollution sources. Various methods have been used and developed to understand pollution sources and the amount of pollution those sources emit. Multivariate receptor modeling seeks to estimate pollution source profiles and pollution emissions from concentrations of pollutants such as particulate matter (PM) in the air. Previous approaches to multivariate receptor modeling make the following two key assumptions: (1) PM measurements are independent and (2) source profiles are constant through time. Notwithstanding these assumptions, the existence of temporal correlation among PM measurements and time-varying source profiles is commonly accepted. In this thesis an approach to multivariate receptor modeling is developed in which the temporal structure of PM measurements is accounted for by modeling source profiles as a time-dependent Dirichlet process. The Dirichlet process (DP) pollution model developed herein is evaluated using several simulated data sets. In the presence of time-varying source profiles, the DP model more accurately estimates source profiles and source contributions than other multivariate receptor model approaches. Additionally, when source profiles are constant through time, the DP model outperforms other pollution receptor models by more accurately estimating source profiles and source contributions.
Degree
MS
College and Department
Physical and Mathematical Sciences; Statistics
Rights
http://lib.byu.edu/about/copyright/
BYU ScholarsArchive Citation
Heaton, Matthew J., "Temporally Correlated Dirichlet Processes in Pollution Receptor Modeling" (2007). Theses and Dissertations. 904.
https://scholarsarchive.byu.edu/etd/904
Date Submitted
2007-05-31
Document Type
Thesis
Handle
http://hdl.lib.byu.edu/1877/etd1861
Keywords
pollution source apportionment, dynamic linear model, dirichlet process, temporal correlation, source profile, time-varying loadings
Language
English