基金This study has been supported by “Research on Chinese Enterprises' R&D Efficiency and Its Influencing Factors” under National Natural Science Foundation of China (70902002), “Research on Beijing Enterprises' R&D Efficiency and Its Influencing Factors: Analysis Based on Cutting-edge” under Beijing Natural Science Foundation (9102019), together with “Program for New Century Excellent Talents in University” under the Ministry of Education and Key Project under the “211 Project” for Central University of Finance and Economics.