Table 1.

Performance Statistics for Each Exposure Estimate, Aggregated Across All In Situ Measurement Sites 1 July 2012–2031 and October 2012

Exposure Estimate	Slope	R 2	Mean Absolute Error (µg m−3)	Mean Bias (µg m−3)
WRF‐Chem	0.67	0.25	11.45	10.22
Kriging	0.70	0.69	2.09	0.00
MODIS AOD	0.01	0.18	–	–
Global ridge regression	0.70	0.69	2.14	0.01
Geographically weighted regression	0.78	0.66	2.40	0.37