, despite sustained progress in scientific knowledge, recent productivity growth in the U.S. has been disappointing. We review … major changes in the American innovation ecosystem over the past century. The past three decades have been marked by a … growing division of labor between universities focusing on research and large corporations focusing on development. Knowledge …

knowledge is an input into internal invention, and thus, more valuable to firms with inventive capability. Using a simple model … of innovation and imitation, we explore how inventive capability affects a firm's R&D investments, and thus whether and … external knowledge as well as the supply of external inventions. In an advance over the literature, we treat firm inventive …

Technical progress increasingly relies on the use of scientific knowledge. But if much of this knowledge is in the …