题 目：An Analysis of Selectivity in the Productivity Evaluation of Biotechnology: An Application to Corn
主讲人：施冠明副教授 （University of Wisconsin-Madison, Department of Agricultural and Applied Economics）
时 间：2012年6月1日 14:00-15:00
地 点：主楼317会议室
主讲人简介：
Associate Professor, UW Madison, Agricultural and Applied Economics and Core Member, The Initiative for Studies in Transformational Entrepreneurship (INSITE) Cluster, UW Madison, School of Business.
Ph.D. University of California at Berkeley. Agricultural & Resource Economics. 2005
B.Econ. Fudan University, Shanghai, PR China. International Finance. 1995
Research interests: Applied Microeconomics, Intellectual Property Rights and Industrial Organization, Production Economics
内容简介：
This paper investigates selectivity bias issues arising in the productivity evaluation of biotech hybrids, with an application to GM corn yield. The analysis is applied to experimental data on Wisconsin corn yields covering the period 1990-2010. Relying on a “Heckman-like” factor that accounts for selectivity, the analysis uncovers evidence of selection bias. It indicates that some of the observed yield advantage associated with GM hybrids is contributed by their conventional genes. This stresses that, even after the widespread adoption of GM corn in the US, traditional breeding still plays an important role in productivity improvements for corn. We also document how rising market concentration of biotech firms has contributed to increasing selectivity bias in corn yield. The impact, however, is counteracted by the negative effect of rising adoption rate of GM corn on selectivity bias.