Growth through Heterogeneous Innovations

• 成果类型: Article
• 署名作者: Akcigit, Ufuk; Kerr, William R.
• 署名单位: University of Chicago; National Bureau of Economic Research; Center for Economic & Policy Research (CEPR); Harvard University; National Bureau of Economic Research
• 刊物名称: JOURNAL OF POLITICAL ECONOMY
• ISSN/ISSBN: 0022-3808
• DOI: 10.1086/697901
• 发表日期: 2018
• 页码: 1374-1443
• 关键词: research-and-development; knowledge spillovers; patent citations; size distribution; life-cycle; count data; firm size; COMPETITION; EVOLUTION; industry

摘要

We build a tractable growth model in which multiproduct incumbents invest in internal innovations to improve their existing products, while new entrants and incumbents invest in external innovations to acquire new product lines. External and internal innovations generate heterogeneous innovation qualities, and firm size affects innovation incentives. We analyze how different types of innovation contribute to economic growth and the role of the firm size distribution. Our model aligns with many observed empirical regularities, and we quantify our framework with Census Bureau and patent data for US firms. Internal innovation scales moderately faster with firm size than external innovation.