A Machine Learning-Based Study of the Effects of Air Pollution and Weather in Respiratory Disease Patients Visiting Emergency Departments

Table 3

General information of atmospheric variables (Mean ± SD).

	2015		2016	2017	Total	P
Weather
Precipitation (mm)		0.090 ± 0.293	0.113 ± 0.441	0.141 ± 0.641	0.115 ± 0.480	0.365
Temperature (°C)		13.614 ± 10.129	13.584 ± 11.023	13.054 ± 10.959	13.418 ± 10.705	0.729
Humidity (%)		59.785 ± 14.714	59.137 ± 13.967	57.744 ± 14.448	58.889 ± 14.391	0.147
Steam pressure (hPa)		11.115 ± 7.508	11.543 ± 8.111	11.058 ± 8.320	11.239 ± 7.983	0.668
Wind speed (m/s)		2.675 ± 0.901	2.276 ± 0.700	2.202 ± 0.684	2.384 ± 0.795	≤0.001
Wind direction (16 direction)		184.226 ± 68.367	199.434 ± 70.907	197.603 ± 64.954	193.760 ± 68.397	0.005
Air pollution
CO	0.575 ± 0.186		0.570 ± 0.152	0.550 ± 0.165	0.565 ± 0.168	0.122
NO2	0.038 ± 0.012		0.038 ± 0.010	0.035 ± 0.011	0.037 ± 0.011	≤0.001
O3	0.020 ± 0.010		0.021 ± 0.010	0.022 ± 0.011	0.021 ± 0.010	0.024
PM10	47.547 ± 37.517		50.446 ± 21.878	47.267 ± 23.633	48.422 ± 28.551	0.249
PM2·5	23.007 ± 11.544		26.154 ± 11.496	24.652 ± 14.119	24.606 ± 12.501	0.003
SO2	0.006 ± 0.001		0.005 ± 0.001	0.005 ± 0.001	0.005 ± 0.001	≤0.001

CO, carbon monoxide; NO₂, nitrogen dioxide; O₃, ozone; PM, Particulate matter; SO2, sulfur dioxide.