This paper examines the sets of feasible allocations in a large class of economic environments in which commitment is impossible (the standard definition of feasibility is adapted to take account of the lack of commitment). The environments feature either memory or money. Memory is defined as...

Typical incomplete markets models in international economics make two assumptions. First, households are not able to fully insure themselves against country-specific shocks. Second, there is a representative household within each country, so that households are fully insured against...

The paper examines the literature that attempts to resolve the equity premium and riskfree rate puzzles. It demonstrates that the puzzles will confront any model of asset prices that relies on three crucial assumptions: preferences have a particular parametric form, asset markets are complete,...

In this paper, I provide a possible explanation of why nominally risk-free bonds are essential in monetary economies. I argue that the role of nominal bonds is to serve as record-keeping devices in intertemporal exchanges of money. I show that bonds can only serve this role if they are illiquid...

This paper considers four models in which immortal agents face idiosyncratic shocks and trade only a single risk-free asset over time. The four models specify this single asset to be private bonds, public bonds, public money, or private money respectively. I prove that, given an equilibrium in...

This paper provides a new rationalization for deposit insurance and systemic disintermediations. I consider an environment in which borrowers face no penalty for failing to repay obligations except the loss of their collateral. I assume that this collateral has aggregate risk. For a subset of...

Total factor productivity (TFP) differs greatly across countries. In this paper, I provide a novel rationalization for these differences. I consider two environments, one in which enforcement is full and the other in which enforcement is limited. In both settings, manufactured goods can be...

We consider an environment in which individuals receive income shocks that are unobservable to others and can privately store resources. We provide a simple characterization of the efficient allocation in cases in which the rate of return on storage is sufficiently high or, alternatively, in...

Much economic activity takes place within the home. Unfortunately, it is difficult to assess the cyclical properties of home production because the available data are too sporadic. Under the assumption that each observation of historical U.S. data on consumption, investment, and hours worked is...