When asset markets are incomplete there are almost always many Pareto improving policy interventions. Remarkably, these interventions do not involve adding any new markets. Focusing on tax policy, I create a framework for proving the existence of Pareto improving taxes, for computing them, and...

A classic characterization of competitive equilibria views them as feasible allocations maximizing a weighted sum of utilities. It has been applied to establish fundamental properties of the equilibrium notion, such as existence, determinacy, and computability. However, it fails for economies...

When asset markets are incomplete there are almost always many Pareto improving policy interventions, provided there are multiple commodities and households. Remarkably, these interventions do not involve adding any new markets. Focusing on tax policy, I create a framework for proving the...

We show that for generic economies, every equilibrium admits Pareto improving monetary policy, even with multiple commodities per state.The main assumption is that asset incompleteness be intermediate, in that household heterogeneity does not exceed the number of assets present and absent.We...

Fixing a risky intertemporal, interagent consumption profile, its quot;social costquot; is the total willingness to pay for smoothing everyone's consumption. It decomposes into a quot;micro costquot; capturing the inefficiency in the distribution of total consumption, risky as it is, and a...