We develop a life-cycle model of the labor market in which different worker-firm matches have different quality and the assignment of the right workers to the right firms is time consuming because of search and learning frictions. The rate at which workers move between unemployment, employment...

In an infinite-horizon economy with matching frictions, I study the efficient assignment between workers of different skill levels and machines of different quality levels. Under some restrictions I show that the efficient allocation assigns a unique machine quality and market tightness to each...

This paper examines the stochastic relationship between money and capital in an economy with spatially separated markets. The new ingredient of the model is that trades between markets may be desirable but are eliminated by market separation. When this cross-market friction is operative,...

We examine a search money model in which there is a symmetric coincidence of wants in all barter matches. However, when bargaining outcomes are asymmetric across matches, the barter economy is inefficient. Then a robust monetary equilibrium exists provided that money holders enjoy adequate...