The APEC blue endeavor: Causal effects of air pollution regulation on air quality in China

Estimating the causal effects of China's environmental regulation on air quality is of great importance for developing effective and efficient policies. Our study first compared the evaluation approaches used in applied econometrics, and environmental science and engineering. It then assessed the environmental effectiveness of the recently strengthened air pollution regulation in China, by developing quasi-experimental designs based on the pollution control programs for the APEC Meeting and the Victory-day Parade. We empirically confirmed that the regulation brought a short-term, substantial improvement in air quality in Beijing. Compared with the hypothetical situation in the absence of the programs, the Victory-day Parade regulation reduced AQI by 37.4%, and the daily average concentrations of PM2.5, PM10, O-3, SO2, NO2, and CO by 55.8%, 50.1%, 27.2%, 35.9%, 39.9%, and 28.8%, respectively; the APEC regulation brought down the AQI by 35.9%, and the concentrations of PM2.5, PM10, SO2, NO2, and CO by 41.3%, 48.2%, 56.5%, 38.9%, and 35.5%, respectively. Further analyses of 70 cities in North China found that the effects in the assigned key control areas were greater than those in the ordinary control areas. Our study enriches the assessments of the regulatory experimentations for the two important events, and demonstrates the strengths of using the quasi-experimental approach to execute quick and reliable ex post evaluation of environmental regulation in China. It also summarizes our first-step, exploratory progress in the challenging communication among the policy-evaluation perspectives and methodologies of different disciplines. (C) 2017 Elsevier Ltd. All rights reserved.