Table 1. Summary of the Source, Target, and Validation Data.

			NO2			UFP
data set	data source	time frame	measured road segments	# drive passa (mean)	mean concentrations (μg/m3)	measured road segments	# drive passa (mean)	mean concentrations (particles/cm3)
Amsterdam mobile data	AirView mobile campaign	10 months 160 collection days 2019-05-20 to 2020-02-27	47,670	6.8	28.6	47,327	5.8	32,822
Copenhagen mobile data	AirView mobile campaign	30 collection days 2019-02-11 to 2019-03-26	13,736	1.7	22.4	20,495	1.9	15,186
Rotterdam mobile data	Ri-Urban project	30 collection days 2022-11-16 to 2022-12-22	59,269	1.8	23.5	61,272	1.8	23,172
external fixed-site validation data (Palmes)	GGDc	10 months 160 collection days May 2019 to March 2020, Amsterdam	82 sites	N.A.b	28.0	not available
model comparison	Google insightsd	Amsterdam predictions from mixed-effect model based on 160 collection days	47,962	N.A.b	28.8	47,962	N.A.b	22,175

^aDrive pass is defined as the number of different dates of drive passing.

^bN.A.: not applicable.

^cGGD: Amsterdam Municipal Health Service.

^dPublic access via: https://insights.sustainability.google/labs/airquality