Du, Xiaodong

By: Yu, Charng-Jiun; Du, Xiaodong; Phaneuf, Daniel
We quantify the impact of the Clean Water Act (CWA) on farm waste management practices of U.S. dairy concentrated animal feeding operations (CAFOs), including storage capacity, land application, and manure removal. We employ a double-hurdle model to examine how dairy farmers adjusted their practices in response to a major policy revision of the CWA in 2003. We find that the revision significantly increased the adoption rate of nutrient management plan (NMP) among dairy CAFOs. The results suggest that the CWA had a heterogeneous and limited impact on dairy CAFOs' waste management practices.
By: Jang, Heesun; Du, Xiaodong
Using patent counts and citation data from 1977 to 2011, we explore the determining factors of innovative activities of the U.S. biofuel industry.We take into account both demand-side factors— such as crude-oil price, government R&D expenditure on biofuel, and federal-level support policies—and supply-side factors, represented by constructed knowledge stocks, to quantify the effects on biofuel-related innovations. The citation generation process is quantified using patent citation records and the estimates are used to construct the simple and weighted stocks of knowledge with weights of patent productivity. We confirm that both the demand and supply factors have positive and statistically significant effects on technological biofuel innovations in the United States.