This paper presents a simple North-South model of endogenous growth, based on learning by doing, which is consistent with the following empirical observations: (i) the price of investment goods relative to consumption goods has been falling for the last 40 years in most industrialized countries,...

We show that the two-sector version of the AK model proposed by Rebelo (1991) can be read as an endogenous growth extension of Greenwood, Hercowitz and Krusell (1997). By confining constant returns to capital to the investment goods sector, the model generates endogenously the secular downward...

Cities exist because of the productivity gains arising from clustering production and workers, a process called agglomeration. How important is agglomeration for aggregate growth? This paper constructs a dynamic stochastic general equilibrium model of cities and uses it to estimate the effect of...