This paper, an extension of the Presidential Address to the International Economic Association, evaluates alternative strands of macro-economics in terms of the three basic questions posed by deep downturns: What is the source of large perturbations? How can we explain the magnitude of...

This paper considers two central problems in our statistical frameworks which impair the ability to use wealth to assess economic sustainability or the impacts of economic downturns. Some increases in wealth may reflect increased economic rents--in particular, land and exploitation rents--and...

A significant amount of the increase in the wealth income ratio in recent decades is due to an increase in the value of land. We present a series of models that explain why land prices may have increased. These models help us understand the increase in both the wealth income ratio and wealth...

A second extension analyzes the effects of land. We ask whether land holding displaces the holding of capital, resulting in workers being worse off. A tax on land, while reducing the value of land, leaves unchanged the capital-labor ratio, output per capita, and wages. But the tax reduces the...

Among the key results are: (i) The magnitude of wealth inequality does not, in general depend on the difference between the rate of interest (r) and the rate of growth (g); the former is itself an endogenous variable that needs to be explained. In the standard generalization of the Solow model,...

Explaining why the concepts of "capital" and "wealth" are distinct, we show that appropriately defined aggregates for wealth may be (and in the case of some countries appear to be) moving in opposite directions

This paper analyzes equilibrium, dynamics, and optimal decisions on the factor bias of innovation in a model of induced innovation. In a model with full employment, we show that (a) if the elasticity of substitution is always less than or greater than unity, there is a unique steady state...

Frank Ramsey's classic paper "A contribution to the theory of taxation" gave rise to the modern theory of optimal taxation. This paper traces the literature that grew out of Ramsey's 1927 paper and assesses which of its key insights has proven robust. Though the path breaking work of Peter...

Macroeconomics has not done well in recent years: The standard models didn't predict the Great Recession; and even said it couldn't happen. After the bubble burst, the models did not predict the full consequences

It concludes by constructing a simple model in which knowledge flows slowly across national borders but moves easily within borders. We show there is a leadership-followership equilibrium, in which some countries are leaders, others are followers. Contrary to Solow's analysis, there need not be...