Correlating vehicle accident number to weather conditions and air quality index in Beijing

Vehicle accident data from insurance statistics, meteoro logic data and air quality index (EQI) from official environmental monitorstations were used to conduct Pearson product-momentcorrelation analysis, in order to reveal impact of temperature, precipitation and AQI on vehicle accidents in Beijing. February was found to be the month with fewest vehicle accidents in 2015, but October had the most accidents, accounting for 10% of total annual vehicle accidents. Analysis further showed that both daily mean temperature and precipitation correlated negatively to daily vehicle accident number, but daily AQI correlated positively. Seasonal and monthly data analysis showed some difference to yearly data analysis. No significant correlation was found between daily precipitation and vehicle accident number. Daily accident number was found to correlate positively with mean daily temperature in summer. To improve in-car air quality in summer, to improve road conditions in autumn and winter, to limit vehicle number on the road during heavy pollution, and to forecast accident risks, will all help to reduce accident number and relieve traffic jam.