Climate policy is complicated by the considerable compounded uncertainties over the costs and benefits of abatement. We don't even know the probability distributions for future temperatures and impacts, making cost-benefit analysis based on expected values challenging to say the least. There are...

Any economic analysis of climate change policy requires some model that describes the impact of warming on future GDP and consumption. Most integrated assessment models (IAMs) relate temperature to the level of real GDP and consumption, but there are theoretical and empirical reasons to expect...

Focusing on tail effects, I incorporate distributions for temperature change and its economic impact in an analysis of climate change policy. I estimate the fraction of consumption w*(tau) that society would be willing to sacrifice to ensure that any increase in temperature at a future point is...

In merger analysis and other antitrust settings, risk is often cited as a potential barrier to entry. But there is little consensus as to the kinds of risk that matter - systematic versus non-systematic and industry-wide versus firm-specific - and the mechanisms through which they affect entry....

I discuss the antitrust suit brought by the U.S. Department of Justice against Visa and MasterCard in 1998. Banks that issue Visa cards are free to also issue MasterCard cards, and vice versa, and many banks issue the cards of both networks. However, both Visa and MasterCard had rules...

In a world of certainty, the design of environmental policy is relatively straightforward, and boils down to maximizing the present value of the flow of social benefits minus costs. But the real world is one of considerable uncertainty -- over the physical and ecological impact of pollution,...

Sunk costs play a central role in antitrust economics, but are often misunderstood and mismeasured. I will try to clarify some of the conceptual and empirical issues related to sunk costs, and explain their implications for antitrust analysis. I will be particularly concerned with the role of...

The regulation of telecommunications, railroads, and other network industries has been based on mandatory unbundling and facilities sharing - entrants have the option to lease part or all of incumbents' facilities if and when they desire, at rates determined by regulators. This flexibility is of...

This paper addresses the impact on investment incentives of the network sharing arrangements mandated by the Telecommunications Act of 1996, with a focus on the implications of irreversible investment. Although the goal is to promote competition, the sharing rules now in place reduce incentives...