What should be the West's top priority for climate-change policy? This article is a revised and updated version of my talk to the Potsdam Global Sustainability Symposium (which drafted the Potsdam Declaration presented to the 2007 UN Climate Change Conference in Bali).

We study 30 vintages of FRB/US, the principal macro model used by the Federal Reserve Board staff for forecasting and policy analysis. To do this, we exploit archives of the model code, coefficients, baseline databases and stochastic shock sets stored after each FOMC meeting from the model’s...

In this paper we propose a new way to formulate optimal policy based on a quadratic intertemporal welfare function where the dynamic constraint is based on a VAR model of the economy which we call the PVAR method. We argue that the VAR under control should not be derived simply by replacing the...

We analyze a dynamic stochastic general-equilibrium (DSGE) model with an externality---through climate change---from using fossil energy. A central result of our paper is an analytical derivation of a simple formula for the marginal externality damage of emissions. This formula, which holds...

Researchers debate whether environmental investments reduce firm value or can actually improve financial performance. We provide some first evidence on shareholder wealth effects of voluntary corporate environmental initiatives. Companies announcing membership in Climate Leaders and Ceres - two...

This paper proposes a new approach for modeling investor fear after rare disasters. The key element is to take into account that investors' information about fundamentals driving rare downward jumps in the dividend process is not perfect. Bayesian learning implies that beliefs about the...

This paper shows that absent a commitment technology, central banks can nevertheless achieve the (timeless-)optimal commitment equilibrium if they are delegated with an objective function that is different from the societal one. In a prototypical forward-looking New Keynesian model, I develop a...

Using a calibrated OLG model with several sources of uncertainty we find that the impact of ageing and of reform of social security upon the demand for housing and the level of owner occupation is substantial. The overall structure of household asset holdings – in particular the split between...

This Paper studies the optimal policies of borrowers (firms or individuals) who may default subject to default costs, and analyses the asset pricing implications. Borrowers defaulting under adverse economic conditions may, despite incurring default costs, emerge as wealthier than non-borrowers...

We consider a general class of nonlinear optimal policy problems involving forward-looking constraints (such as the Euler equations that are typically present as structural equations in DSGE models), and show that it is possible, under regularity conditions that are straightforward to check, to...