A two-country model of growth is developed with exogenous fluctuations in the rate of technological progress. Technological growth in the leading country follows a random walk, while in the lagging country the rate of advance depends on the technological distance between the two countries and...

We reassess Mankiw, Romer and Weil's [mrw] version of the Solow model using, as did mrw, cross-sectional data to estimate the steady-state equation governing income per capita levels. The model fails in two critical areas. First, plausible factor shares obtained by mrw are not robust to the...

We modify Romer's [1990] model of endogenous technological change, incorporating population growth, capital depreciation and diminishing returns to R&D, and removing scale effects. The steady-state of the model is characterized by a system of non-linear simultaneous equations in which income per...