文摘
This thesis studies economic growth from the perspective of the firm, with an emphasis on the role of information diffusion. In chapter 1, I explore the growth of firms and economies as the result of information disseminating about existing technologies. The least productive agents in an economy can be vital in generating growth by spurring technology diffusion. I develop an analytically tractable model where growth is created as the result of a positive externality from risk taking by firms at the bottom of the productivity distribution imitating more productive firms. Heterogeneous firms choose to produce or pay a cost and search within the economy to upgrade their technology. Sustained growth comes from the feedback between the endogenously determined distribution of productivity, as evolved by past search decisions, and an optimal forward-looking search policy. The growth rate depends on characteristics of the productivity distribution, with a thicker tailed distribution leading to more growth. In chapter 2, I explore the growth of firms, industries, and economies through diffusion of information about products to consumers. Does expanding consumer awareness of new products explain firm growth and the industry life cycle? Output in many industries grows slowly and eventually stabilizes, while the market valuation peaks and then drops -- all without significant changes in productivity. To explain this pattern, I introduce a mechanism where consumers with heterogeneous preferences slowly become aware of differentiated products in the industry. As the industry evolves and consumers meet more firms, growing awareness generates two countervailing forces on firm profits: 1) market power decreases due to more intense price competition, and 2) demand increases due to customers sorting into their preferred firms. Consequently, if increased awareness results in a strong enough reduction in market power, profits and valuations peak and then decrease, even as output grows monotonically. When aggregated across firms in an industry, the slow expansion of product awareness looks like a capacity constraint or an adjustment cost, while the sorting of customers into preferred products gives the illusion of productivity or quality growth.