Tab. 6 Parameters of benzene map

Linear regression model + interpolation of residuals Benzene
annual average
background traffic
c (constant) 2.1 1.5
a1 (altitude) -0.002  
a2 (model SYMOS CO)   0.04
range [km] 28  
nugget 0  
partial sill 0.2  
weight IDW   2
RMSE [µg.m-3] 0.3 0.3
relat. RMSE [%] 22 15