Self-learning Kinetic Monte-Carlo method: application to Cu(111)

We present a novel way of performing kinetic Monte Carlo simulations which does not require an {\it a priori} list of diffusion processes and their associated energetics and reaction rates. Rather, at any time during the simulation, energetics for all possible (single or multi-atom) processes, within a specific interaction range, are either computed accurately using a saddle point search procedure, or retrieved from a database in which previously encountered processes are stored. This self-learning procedure enhances the speed of the simulations along with a substantial gain in reliability because of the inclusion of many-particle processes. Accompanying results from the application of the method to the case of two-dimensional Cu adatom-cluster diffusion and coalescence on Cu(111) with detailed statistics of involved atomistic processes and contributing diffusion coefficients attest to the suitability of the method for the purpose.Comment: 18 pages, 9 figure

An Exceptionally Simple Theory of Industrialization

Historically, industrialization has been associated with falling relative returns to skills. This fact is at odds with most theories of industrialization, which tend to imply rising skill premia as natural concomitants to economic growth. This paper develops a very simple model of historical growth to help solve this puzzle. Assuming that human capital is both a consumption good and an investment good, the model demonstrates how rising education levels, non-monotonic fertility rates, and falling skill premia can all be explained within one theory.

Human Capital and Technological Transition – Insights from the U.S.Navy

This paper explores the eects of human capital on workers during the latter 19th century by examining the specic case of the U.S. Navy. During this time, naval ocers belonged either to a regular or an engineer corps and had tasks assigned for their specialized training and experience. To test the eects of specialized skills on career performance, we compile educational data from original-source Naval Academy records for the graduating classes of 1858 to 1905. We merge these with career data extracted from ocial Navy registers for the years 1859 to 1907. This compilation comprises one of the longest and earliest longitudinal records of labor market earnings, education and experience of which we are aware. Our results suggest that wage premia for \engineer-skilled" ocers rapidly deteriorated over their careers; more traditionally skilled ocers were better compensated and promoted more frequently as their careers progressed. This compelled those with engineering skills to leave the service early, contributing to the Navy's failure to keep up with the technological frontier of the time.

The Road Not Taken - What Is The “Appropriate” Path to Development When Growth is Unbalanced?

This paper develops a model that endogenizes both directed technologies and demography. Potential innovators decide which technologies to develop after considering available factors of production, and individuals decide the quality and quantity of their children after considering available technologies. This interaction allows us to evaluate potentially divergent development paths. We nd that exogenous unskilled-labor biased technological growth can induce higher fertility and lower education, inhibiting overall growth in per person income. However, if technical progress is locally endogenous, increases in the overall workforce caused by unskilled intensive technological progress can make R&D more protable; this can actually induce more income growth can the alternative, skill-intensive path.

The Appropriate Technology Frontier - Lessons for the Developing World

This paper presents a model of a developing economy that endogenizes both technological biases and demographic trends. As knowledge diffuses from foreign R&D-producing regions, potential innovators decide which technologies to develop after considering available factors of production, and individuals decide the quality and quantity of their children after considering available technologies. This interaction creates multiple growth paths- some economies develop labor-intensive techniques and expand the pool of unskilled labor; others grow into societies of highly skilled individuals and expanding outputs per capita. I find that if developing countries wish to achieve good prospects for income convergence, they should promote the flow of knowledge from the most developed regions, even if this results initially in a technology-skill mismatch. Such knowledge flows are more likely to promote the twin growths in human capital and technologies characteristic of the biggest economic success stories.