Equilibria and optima generally differ in imperfectly competitive markets. While this is well understood theoretically, it is unclear how large the welfare distortions are in the aggregate economy. Do they matter quantitatively? To answer this question, we develop a multi-sector monopolistic...

Headquarters and their specialized component suppliers have a vital interest in establishing long-term collaborations. When formal contracts are not enforceable, such efficiency-enhancing cooperations can be established via informal agreements, but relational contracts have been largely ignored...

We characterize the equilibrium and optimal resource allocations in a general equilibrium model of monopolistic competition with multiple asymmetric sectors and heterogeneous firms. We first derive general results for additively separable preferences and general productivity distributions, and...

We develop a general equilibrium model of international trade with heterogeneous firms, where countries can invest into basic research to improve their technological potential. These research investments tighten firm selection and raise the average productivity of firms in the market, thereby...

We develop a theory of a firm in an environment with incomplete contracts. The firm's headquarter decides on the complexity, the organization, and the global scale of its production process. Specifically, it decides: i) on the mass of symmetric intermediate inputs that are part of the value...

In this paper we show that the double Pareto lognormal (DPLN) parameterization provides an excellent fit to the overall US city size distribution, regardless of whether cities are administratively defined Census places or economically defined area clusters. We then consider an economic model...

Recent studies indicate that firms often outsource standard and simple tasks, while keeping complex and important inputs inside their boundaries. This observation is difficult to reconcile with the property rights approach of the firm, which suggests that important components should be...

In this paper we show that the double Pareto lognormal (DPLN) parameterization provides an excellent fit to the overall US city size distribution, regardless of whether cities are administratively defined Census places or economically defined area clusters. We then consider an economic model...

Recent studies indicate that firms often outsource standard and simple tasks, while keeping complex and important inputs inside their boundaries. This observation is difficult to reconcile with the property rights approach of the firm, which suggests that important components should be...

We analyze the effects of the unprecedented rise in trade between Germany and the East - China and Eastern Europe - in the period 1988-2008 on German local labor markets. Using detailed administrative data, we exploit the cross-regional variation in initial industry structures and use trade...