R/ecat_and_scaling_functions.R
calculate_ecat.Rdcalculate_ecat() uses a land use regression model developed by Dr. Patrick Ryan
based on ambient air sampling in Cincinnati, OH between 2001 and 2005 to estimate
exposure to elemental carbon attributable to traffic (ECAT) at point locations in
the area specified by latitude and longitude. The model predictors include elevation,
truck traffic within 400 meters, and length of bus routes within 100 meters. Returned
ECAT values are in micrograms per cubic meter.
calculate_ecat(locations, return.LU.vars = FALSE)
| locations | Data.frame with columns 'id', 'lat', and 'lon' at minimum. |
|---|---|
| return.LU.vars | When |
If `return.LU.vars` = `FALSE`, a numeric vector of ECAT estimates (ug/m3) is returned. If `return.LU.vars` = `TRUE`, the `locations`` data.frame with additional columns for E CAT values and the land use predictors used to generate the ECAT values is returned.
ECAT will be missing if point is outside the 7-county area (OH: Hamilton, Butler, Warren, Clermont; KY: Campbell, Kenton, Boone)
Ryan, P.H., G.K. LeMasters, P. Biswas, L. Levin, S. Hu, M. Lindsey, D.I. Bernstein, J. Lockey, M. Villareal, G.K. Khurana Hershey, and S.A. Grinshpun. 2007. "A Comparison of Proximity and Land Use Regression Traffic Exposure Models and Wheezing in Infants." Environmental Health Perspectives 115(2): 278-284. https://doi.org/10.1289/ehp.9480
my_data <- data.frame(id = 1:3, lat = c(39.19674, 39.12731, 39.28765), lon = c(-84.58260, -84.52700, -84.51017)) ecat_est <- calculate_ecat(my_data, return.LU.vars = FALSE)#> Warning: The `raster` package has been attached to the global environment, masking dplyr::select()ecat_est <- calculate_ecat(my_data, return.LU.vars = TRUE)#> Warning: The `raster` package has been attached to the global environment, masking dplyr::select()