Supply shocks played an important role in macroeconomic fluctuations during the 1970's. Supply shocks are also increasingly important in Keynesian and neo-classical models of the business cycle. This paper is a short survey of these theoretical models. It also discusses the history of supply...

A firm may acquire additional caoital input by purchasing new capital or by increasing the utilization of its current capital. The margin between capital accumulation and capital utilization is studied in a model of dynamic factor demand where the firm chooses capital, labor, and their rates of...

A model of the dynamically interrelated demand for capital and labor is specified and estimated. The estimates are of the first-order conditions of the firm's problem rather than of the closed-form decision rules. This use of the first-order conditions allows a random rate of return and a...

Older wealthholders spend down assets much more slowly than predicted by classic life-cycle models. This paper introduces health-dependent utility into a model in which preferences for bequests, expenditures when in need of long-term care (LTC), and ordinary consumption combine with health and...

Labor supply is unresponsive to permanent changes in wage rates. Thus, income and substitution effects cancel, but are they both close to zero or both large? This paper develops a theory of labor supply where income and substitution effects cancel, taking into account optimization over time,...

Measured productivity growth increased substantially during the second half of the 1990s. This paper examines whether this increase owes to an increase in the rate of technological change or whether it can be explained by non-technological factors relating to factor utilization, factor...