We analyze recent contributions to growth theory based on the model of expanding variety of Romer [Romer, P. (1990). “Endogenous technological change”. Journal of Political Economy 98, 71–102]. In the first part, we present different versions of the benchmark linear model with imperfect...

We study the gains from trade in a model with oligopolistic competition, heterogeneous firms and innovation, and provide a formula to decompose the mechanism. The new insight we provide is that market concentration can be a welfare-relevant feature of market power above and beyond markup...

In this paper, we present a standard quality ladders endogenous growth model with one significant new assumption, that it takes time for firms to learn how to export. We show that this model without Melitz-type assumptions can account for all the evidence that the Melitz (2003) model was...

We investigate the impact of incremental trade liberalization in a dynamic model of endogenous growth with heterogeneous firms and costly trade. Growth originates from horizontal specialization and the steady state productivity growth rate is positive. Innovations require costly R&D and are...

In this paper, we present a standard quality ladders endogenous growth model with one significant new assumption, that it takes time for firms to learn how to export. We show that this model without Melitz-type assumptions can account for all the evidence that the Melitz (2003) model was...

In this paper I build a North-South model of international trade, economic growth and search-frictional unemployment in the North. Growth is driven by a process of creative destruction in the North followed by imitation in the South. I study the effects of intellectual property rights protection...

We study the gains from trade in an economy with oligopolistic competition, firm heterogeneity, and innovation. Oligopolistic competition together with free entry make markups responsive to firm productivity and trade costs. Lowering trade costs reduces markups on domestic sales but increases...

This paper studies the effect of competition on firm innovation by developing a discrete-time endogenous growth model where multi-product firms do two types of innovation subject to friction in technology spillovers. Firms improve their existing products through internal innovation while...

We study the gains from trade in a model with oligopolistic competition, heterogeneous firms and innovation, and provide a formula to decompose the mechanism. The new insight we provide is that market concentration can be a welfare-relevant feature of market power above and beyond markup...

Growth and business cycles have a long tradition of being studied separately. However, events such as the Great Recession raise concerns that severe downturns may have detrimental implications for growth. If so, what policies may help alleviate such long-lasting effects of large recessions? To...