This paper provides a novel rationale for the regulation of market size when heterogeneous firms compete. A regulator seeks to maximize total welfare by choosing the number of firms allowed to enter the market, e.g. by issuing a certain number of licenses. Opening up the market for more firms...

We extend structural gravity models of bilateral trade flows to oligopolistic competition. We show that conventional gravity estimates do not only reflect trade costs but also market power. Our simple estimation procedure generalizes the standard gravity model and disentangles exogenous trade...

The number of preferential trade agreements has greatly increased over the past two decades, yet most existing bilateral arrangements take the form of free trade areas, and less than ten percent can be considered to be fully fledged customs unions. This paper develops a political economy model...