A satisfactory account of the postwar growth experience of the United States should be able to come to terms with the following three facts: -Since the early 1970's there has been a slump in the advance of productivity. -The price of new equipment has fallen steadily over the postwar period....

This paper describes a pure-exchange, continuous-time economy with two heterogeneous agents and complete markets. A novel feature of the economy is that agents perceive some security returns as ambiguous in the sense often attributed to frank Knight. The equilibrium is described completely in...

How much technological change progress has there been in structures? An attempt is made to measure this using panel data on the age and rents of buildings. The data are interpreted with the help of a vintage capital model where buildings are replaced with some chosen periodicity. The key is a...