Many developing countries depend crucially on open-access renewable natural resources (NR). Trade is generally viewed as hurting the long-term health of NR in commodity-exporting countries. I examine whether trade might be beneficial in the case of population growth. Dynamic general equilibrium...

In most dynamic traffic congestion models, congestion tolls must vary continuously over time to achieve the full optimum. This is also the case in Vickrey's (1969) 'bottleneck model'. To date, the closest approximations of this ideal in practice have so-called 'step tolls', in which the toll...

This paper studies the design of sin taxes when firms exercise market power. We outline an optimal tax framework that highlights how market power impacts the efficiency and redistributive properties of sin taxation, and quantify these effects in an application to sugar-sweetened beverage...

We estimate the marginal external congestion cost of motor-vehicle travel for Rome, Italy, using a methodology that accounts for hypercongestion (a situation where congestion decreases a road's throughput). We show that the external cost - even when roads are not hypercongested - is substantial,...