In this paper we measure the extent to which countries are converging in per capita productivity levels. We formally define convergence in a time series analytical context, derive the necessary and sufficient conditions and introduce a cluster analytical procedure that enables us to distinguish...

We examine the diffusion of more than twenty technologies across twenty-three of the world ’s leading industrial economies. Our evidence covers major technology classes such as textile production, steel manufacture, communications, information technology, transportation, and electricity for...

Since 1968, the ratio of stock market capitalization to GDP has varied by a factor of 5. In 1972, the ratio stood at above unity, but by 1974, it had fallen to 0.45 where it stayed for the next decade. It then began a steady climb, and today it stands above 2. We argue that the IT revolution was...

We construct a price index with weights on the prices of different PCE goods chosen to minimize the welfare costs of nominal distortions: a cost-of-nominal-distortions index (CONDI). We compute these weights in a multisector New Keynesian model with time-dependent price setting, calibrated using...

Since 1968, the ratio of stock market capitalization to GDP has varied by a factor of 5. In 1972, the ratio stood at above unity, but by 1974, it had fallen to 0.45 where it stayed for the next decade. It then began a steady climb, and today it stands above 2. ; We argue that the IT revolution...

We introduce a tractable model of endogenous growth in which the returns to innovation are determined by the technology adoption decisions of the users of new technologies. Technology adoption involves an implementation investment that determines the initial productivity of a new technology....

While homeland security is widely seen as an important national objective, the costs of this effort are not well understood. An analysis of public and private expenditures on homeland security shows that overall spending rose by $44 billion between 2001 and 2005?a clear increase but one that...