This paper shows that there can be equilibria in which exchange rates display randomness unrelated to fundamentals. This is demonstrated in the context of a two currency, one good model, with three agent types and cash-in-advance constraints. A crucial feature is that the type i agents, for i=l, 2, must satisfy a cash—in-advance constraint by holding currency i, while type 3 agents can satisfy it by holding either currency. It is shown that real allocations vary across the multiple equilibria if markets for hedging exchange risk do not exist and that the randomness is innocuous if complete markets exist.

Many kinds of economic behavior involve discrete and occasional individual choices. Despite this, econometric partial adjustment models perform relatively well at the aggregate level. Analyzing the classic employment adjustment problem, we show how such microeconomic adjustment is well described by a new form of partial adjustment model that aggregates the actions of heterogeneous producers.

We develop a model where individual establishments infrequently alter the sizes of their workforces because such adjustments involve fixed costs. In the market equilibrium, employment responses to aggregate disturbances include changes both in target employments selected by individual establishments and in the measure of establishments actively undertaking adjustment. Yet the model retains a partial adjustment flavor in its aggregate responses. Moreover, in contrast to existing discrete adjustment models, our generalized partial adjustment model is sufficiently tractable to allow general equilibrium analysis, and it naturally extends to accommodate persistent differences in productivity across establishments in general equilibrium.