Chih-Sheng Hsieh, PhD, Ohio State University at 2013. His research interests span over labor economics, health economics, and social networks. In particular, he works on endogenous selection issues inherited in social interaction studies. Besides, he studies empirical network formation. He develops an empirical network formation model to accommodate various important features from observed network data, such as homophily in characteristics, behaviors, as well as link dependence. He applies the model to study formation of students' friendship networks, firms' R&D networks, and scientific co-author networks. His research has been published in Quantitative Economics, Journal of Applied Econometrics, Regional Science and Urban Economics, and others.