This article investigates the main sources of heterogeneity in regional efficiency. We estimate a translog stochastic frontier production function in the analysis of Spanish regions in the period 1964-1996, to attempt to measure and explain changes in technical efficiency. Our results confirm...

We analyze recent contributions to growth theory based on the model of expanding variety of Romer (1990). In the first part, we present different versions of the benchmark linear model with imperfect competition. These include the “labequipment” model, labor-for-intermediates” and...

For the standard kernel density estimate, it is known that one can tune the bandwidth such that the expected L1 error is within a constant factor of the optimal L1 error (obtained when one is allowed to choose the bandwidth with knowledge of the density). In this paper, we pose the same problem...

We postulate a two-region world, comprised of North (calibrated after the US) and South (calibrated after China). Our optimization results show the compatibility of the following three desiderata: (1) Global CO2 emissions follow a conservative path that leads to the stabilization of...

We continue the development of a method for the selection of a bandwidth or a number of design parameters in density estimation. We provide explicit non-asymptotic density-free inequalities that relate the $L_1$ error of the selected estimate with that of the best possible estimate, and study in...

We use aggregate GDP data and within-country income shares for the period 1970-1998 to assign a level of income to each person in the world. We then estimate the gaussian kernel density function for the worldwide distribution of income. We compute world poverty rates by integrating the density...

Let a class $\F$ of densities be given. We draw an i.i.d.\ sample from a density $f$ which may or may not be in $\F$. After every $n$, one must make a guess whether $f \in \F$ or not. A class is almost surely testable if there exists such a testing sequence such that for any $f$, we make...

How do the liquidity functions of banks affect investment and growth at different stages of economic development? How do financial fragility and the costs of banking crises evolve with the level of wealth of countries? We analyze these issues using an overlapping generations growth model where...

We construct and estimate a unified model combining three of the main sources of cross-country income disparities: differences in factor endowments, barriers to technology adoption and the inappropriateness of frontier technologies to local conditions. The key components are different types of...