Technological advance is often embodied in capital inputs. This paper develops a model where capital innovations occur on two margins: (1) vertically, where a capital input becomes more productive at a given task; and (2) horizontally, where a capital input replaces labor at a given task. These...

This paper provides a primer on the fiscal implications of climate change, in particular the policies for responding to it. Many of the complicated challenges that arise in limiting climate change (through greenhouse gas emissions mitigation), and in dealing with the effects that remain (through...

Great scientific output typically peaks in middle age. A classic literature has emphasized comparisons across fields in the age of peak performance. More recent work highlights large underlying variation in age and creativity patterns, where the average age of great scientific contributions has...

Climate change is an externality problem—so the challenges that arise in limiting it and dealing with the effects that remain are largely fiscal. The structure of the problem, however, and the uncertainty which surrounds it, make the design of proper policy responses particularly complex. This...

What are the individual rewards to working in teams? This question extends across many production settings but is of long-standing interest in science and innovation, where the "Matthew Effect" suggests that eminent team members garner credit for great works at the expense of less eminent team...

Assassinations are a persistent feature of the political landscape. Using a new data set of assassination attempts on all world leaders from 1875 to 2004, we exploit inherent randomness in the success or failure of assassination attempts to identify assassination’s effects. We find that, on...