搜索结果: 1-1 共查到“信息经济学 Surveys”相关记录1条 . 查询时间(0.105 秒)
Did R&D Firms Used to Patent?Evidence from the First Innovation Surveys
Research and Development Patents Surveys Innovation and Invention Geographic Location
2015/5/13
Matching 2,777 R&D firms in surveys conducted by the National Research Council between 1921 and 1938 with U.S. patents reveals that 59 percent of all firms and 88 percent of publicly-traded firms pate...