Grey relational analysis for the AQI of Beijing, Tianjin, and Shijiazhuang and related countermeasures

Purpose The purpose of this paper is to explore the relationship among the air quality index (AQI) of Beijing-Tianjin-Shijiazhuang region and find countermeasures to control the pollution situation. Design/methodology/approach This study used the grey convex relation model to calculate the grey correlation degree through the AQI of Beijing-Tianjin-Shijiazhuang region. Findings By analyzing the calculation results among the three cities, it was concluded that the air quality of the three cities is closely related. Therefore, the Beijing-Tianjin-Shijiazhuang region should collaboratively improve the air quality for common development. Research limitations/implications More approaches may be adopted to calculate the grey correlation degree in the further research studies. Practical implications There exist some practical difficulties in implementing these governance measures. Originality/value The paper gives the countermeasures to control the pollution situation in Beijing-Tianjin-Shijiazhuang region.