Affiliation: | 1. Department of Economics, Duke, 213 Social Sciences building, Box 90097, JHU, CEPR, and NBER, Durham, NC 27708, United States;2. Department of Medicine, Division of Hematology, Brigham and Women’s Hospital, Harvard Medical School, United States;3. Carey Business School, John Hopkins University, JHU Carey, 100 International Drive, Baltimore, MD 21202, United States;1. School of Mathematical Sciences, Peking University, Beijing 100871, P.R. China;2. Key Laboratory of Mathematical Economics and Quantitative Finance, Peking University, Beijing 100871, P.R. China |