Doctoral Dissertation Research in Economics: What Does Innovation Tell Us about Market Concentration?

摘要这个项目探索了企业创新在解释美国经济中最近市场集中度不断提高的趋势中所起的作用。它使用研发(R&D)调查以及生产方面活动的数据来衡量企业层面的创新投入和产出。使用这些详细的数据，该项目记录了创新活动的集中度及其随时间的演变，其中创新集中度是通过企业规模与研发投入和研究生产率之间的关系来衡量的。该项目通过区分两种类型的创新-内部创新和外部创新，进一步研究了创新集中度对总经济的影响。前者衡量的是企业对自身产品的质量改进，后者衡量的是企业试图从其他企业的产品线上获得市场份额的情况。然后，该项目通过基于研发的增长模型的视角，研究创新集中度对每种创新类型的总增长和社会福利的影响。该项目通过每种创新的投入产出比来衡量企业层面的研发生产率。为了区分内部和外部创新，该项目利用了研发调查中关于产品创新的独特信息，以及产品层面的销售数据。然后，通过将研发变量投射到衡量企业规模的指标上，同时控制企业特征，来估计创新集中度。衡量的企业层面创新模式被用来区分基于市场集中度上升的竞争性研发理论。该项目进一步评估了目前经验集中对总体增长和福利的影响。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

AbstractThis project explores the role of firm innovation in explaining the recent trend of increasing market concentration in the U.S. economy. It measures innovation input and output at the firm-level using research and development (R&D) surveys together with data on production-side activities. Using this detailed data, the project documents the concentration of innovation activity and its evolution over time, where the concentration innovation is measured as the relation between firm size and R&D inputs and research productivity. The project further investigates the impact of innovation concentration on the aggregate economy by distinguishing between two types of innovation---internal and external innovation. The former measures firms’ quality improvements of their own products, and the latter measures firms’ attempts to gain market share from other firms’ product lines. The project then studies the impact of innovation concentration on aggregate growth and social welfare for each type of innovation through the lens of an R&D-based growth model. The project measures firm-level R&D productivity by the input-output ratio for each type of innovation. To distinguish between internal and external innovation, the project leverages unique information on product innovation from the R&D surveys together with data on product-level sales. Innovation concentration is then estimated by projecting R&D variables on measures of firm size while controlling for firm characteristics. The measured patterns of firm-level innovation are used to differentiate between competing R&D based theories of rising market concentration. The project further estimates the impact of currently experienced concentration on aggregate growth and welfare.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.