We present a general equilibrium dynamic model that characterizes the gap between optimal and equilibrium fertility and investment in human capital. In the model, the aggregate production function exhibits increasing returns to population arising from specialization but households face the...

There is strong evidence showing that in most countries cities develop sequentially, with the initially largest cities being the first to grow. This paper presents a growth model of optimal city size that rationalizes this growth pattern. Increasing returns to scale is the force that favors...

There exists convincing evidence that democratic countries are less volatile. This conclusion is usually reached with respect to volatility as measured by the standard deviation of annual growth rates of per capita GDP which includes both low and high frequency fluctuations. However, recently...

There is much evidence that less democratic countries experience more high-frequency growth volatility. In this paper we report a similar finding about volatility in the medium term: we find evidence that reversals of trend-growth are sharper and more frequent in non-democracies. Motivated by...

This paper analyzes the process of Internet diffusion across the world using a panel of 199 countries during the time interval 1990-2004. We group countries in two categories, low and high income countries, and show that the Internet diffusion process is well characterized by an S-shape curve...

There is strong evidence showing that in most countries cities develop sequentially, with the initially largest city being the first to grow. This paper presents a growth model of optimal city size that rationalizes this particular growth pattern. Increasing returns to scale is the force that...

This paper uses new estimates of the dates on which different countries have experienced their demographic transition to address two empirical questions. First, I study the importance of different socioeconomic variables on the timing of these transitions. Second, I distinguish between countries...

This paper uses microeconomic data on firms’ money demand and investment in physical capital for the period 1983-2006 to estimate the extent to which variation in the U.S. money supply is an endogenous response to variation in firms’ demand for liquidity. We estimate a simple model in which...