’Effortless Perfection:’Do Chinese Cities Manipulate Air Pollution Data?Abstract:This paper uses unique data on daily air pollution concentrations over the period 2001-2010to test for manipulation in self-reported data by Chinese cities. First, we employ a discontinuitytest to detect the cities that reported dubious pollution data around the cut-off for ”blue-skydays.” Then, we propose a panel matching approach to identify the conditions under whichirregularities may occur. We find that about 50% of cities reported dubious PM10 pollutionlevels that led to a discontinuity at the cut-off. Suspicious data reporting tends to occur ondays when the anomaly is least detectable. Our findings indicate that the official daily airpollution data are not well behaved, which provides suggestive evidence of manipulation.Link to paperAbout the Speaker:Junjie Zhang is an Assistant Professor of Environmental Economics at the School of International Relations and Pacific Studies at the University of California, San Diego. He is a Senior Advisor at the Asia Society and an Associate Editor at the journal of Marine Resource Economics. Zhang completed his Ph.D. in Environmental and Resource Economics from Duke University in 2008. He also holds a B.A. in Environmental Economics and Management from Renmin University of China, a B.S. and a M.S. in Environmental Engineering from Tsinghua University. Zhang’s research centers on empirical issues in environmental and resource economics. He is particularly interested in an interdisciplinary approach that integrates social sciences, engineering and natural sciences to deal with environmental policy problems. His research topics cover air pollution, water resources, climate change, and fisheries. His recent research has focused on the environmental and energy problems in China.