This paper considers a general class of nonlinear rational-expectations models in which policymakers seek to maximize an objective function that may be household expected utility. We show how to derive a target criterion that is: (i) consistent with the model's structural equations, (ii) strong...

Unilateral second-best carbon taxes are analysed in a two-period, two-country model with international trade in final goods, oil and bonds. Acceleration of global warming resulting from a future carbon tax is large if the price elasticities of oil demand are large and that of oil supply is...

Democratic countries with substantial inequality and where people believe that success depends on connections and luck induce political support for high tax rates and generous welfare states. Traditional wisdom is that such policies harm the economy, but there is not much evidence that countries...

Optimal climate policy is studied in a Ramsey growth model. A developing economy weighs global warming less, hence is more likely to exhaust fossil fuel and exacerbate global warming. The optimal carbon tax is higher for a developed economy. We analyze the optimal time of transition from fossil...

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...