You are here:
EPA UNMIX 6.0 USER GUIDE
NORRIS, G. A., R. VEDANTHAM, AND R. M. DUVALL. EPA UNMIX 6.0 USER GUIDE. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-07/089 (NTIS PB2007-112630), 2007.
The goal of this task is to develop methods and models to reduce the uncertainty in quantifying local and regional air pollutant source impacts on ambient samples collected in speciated PM, air toxic, and semi-continuous measurement networks.
The underlying philosophy of Unmix is to let the data speak for itself. Unmix seeks to solve the general mixture problem where the data are assumed to be a linear combination of an unknown number of sources of unknown composition, which contribute an unknown amount to each sample. Unmix also assumes that the compositions and contributions of the sources are all positive. Unmix
assumes that for each source there are some samples that contain little or no contribution from that source. Using concentration data for a given selection of species, Unmix estimates the number of sources, source compositions, and
source contributions to each sample.
Record Details:Record Type: DOCUMENT (PUBLISHED REPORT/USER'S GUIDE)
Organization:U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
NATIONAL EXPOSURE RESEARCH LABORATORY
HUMAN EXPOSURE AND ATMOSPHERIC SCIENCES DIVISION
ENVIRONMENTAL CHARACTERIZATION & APPORTIONMENT BRANCH