Epidemic trade

This paper studies the spread of the Black Death as a proxy for the ow of medieval trade between 1346 and 1351. The Black Death struck most areas of Europe and the wider Mediterranean. Based on a modified version of the gravity model, we estimate the speed (in kilometers per day) of transmission of the disease between the transmitting and the receiving cities. We find that the speed depends on distance, political borders, and on the political importance of a city. Furthermore, variables related to the means of transportation like rivers and the sea, religious seasons such as Lent and Advent, and geographical position are of substantial significance. These results are the first to enable us to identify and quantify key variables of medieval trade ows based on an empirical trade model. These results shed new light on many qualitative debates on the importance and causes of medieval trade. --Trade,Middle Ages,Black Death,Gravity model,Poisson regression

The Italian Job: Match Rigging, Career Concerns and Media Concentration in Serie A

This paper contributes to the literature on competition and corruption, by drawing on records from Calciopoli, a judicial inquiry carried out in 2006 on corruption in the Italian soccer league. Unlike previous studies, we can estimate the determinants of match rigging and use this information in identifying corruption episodes in years in which there are no pending judicial inquiries. We find evidence of corruption activity well before Calciopoli. Career concerns of referees seem to play a major role in match rigging. An implication of our study is that a more transparent selection of the referees and evaluation of their performance is essential in removing incentives to match rigging. Another implication is that in presence of significant "winners-take-all" effects, more competitive balance may increase corruption unless media concentration is also significantly reduced.concentration, corruption, career concerns, random effect ordered probit, Monte Carlo simulations, soccer

TFP Growth in Old and New Europe

Using Solow-Tornqvist residuals as well as two alternative measurements, we present estimates of total factor productivity (TFP) growth in a sample of 30 European economies for the period 1994-2005. In most of Western Europe, we find a deceleration of TFP growth since 2000. However, the economies of New Europe exhibit a higher level of TFP growth overall and have slowed less than those of Old Europe. In the new market economies of Central and Eastern Europe, we nd both high TFP growth as well as acceleration in the second half of the sample. Regression evidence from Western Europe suggests that product market regulation may adversely aect TFP growth and may thus impair convergence.Total factor productivity growth, Solow residual, product and labor market regulation

Solow Residuals without Capital Stocks

For more than fifty years, the Solow decomposition (Solow 1957) has served as the standard measurement of total factor productivity (TFP) growth in economics and management, yet little is known about its precision, especially when the capital stock is poorly measured. Using synthetic data generated from a prototypical stochastic growth model, we explore the quantitative extent of capital measurement error when the initial condition is unknown to the analyst and when capacity utilization and depreciation are endogenous. We propose two alternative measurements which eliminate capital stocks from the decomposition and significantly outperform the conventional Solow residual, reducing the root mean squared error in simulated data by as much as two-thirds. This improvement is inversely related to the sample size as well as proximity to the steady state. As an application, we compute and compare TFP growth estimates using data from the new and old German federal states.Total factor productivity, Solow residual, generalized differences, measurement error, Malmquist index

De experimentos, brujas y demonios, o cómo legitimar lo sobrenatural mediante una epistemología para lo natural

En 1676,Joseph Glanvill publica sus Essays on several subjects. Entre esos ensayos, en aquel titulado "Against Sadducism in the matter of Witchcraft and Appanritons" Glanvill presenta una sene de argumentos contra las proposiciones "saduceas", o escépticas acerca de la existencia de brujas, brujerías y apariciones. El tono del ensayo es teórico en lineas generales, y su finalidad claramente apologética . El autor intenta argumentar a favor de la existencia de brujas y apariciones, mostrando la razonabilidad de ello. Su estrategia será discutir lo que él llama "prejuicios" que sostienen la inexistencia de brujas, y que él teme que conlleven a una ulterior negación de lo espiritual en general, considerando tales prejuicios saduceos como la "antesala del ateísmo" La estrategia planteada en el ensayo no expone toda la intención del autor Glanvill sostendrá que, considerando las posiciones filosóficas como meras hipótesis probables, el ateísmo, como posición filosófica, no ha sido suficientemente refutado. Harán falta "cuestiones de hecho", que prueben la existencia de un mundo de espíritus además de su razonabilidad. La empresa de refutar al ateísmo se debe completar con una metodología que adecuadamente establezca tales cuestiones de hecho

Ascética de la vida experimental: la búsqueda paciente de la verdad dificil

Plantearemos posibles conexiones entre los escritos éticos y devocíonales que Boyle compusiese entre sus 19 y 24 años, las justificaciones que sustentaban su práctica de la filosofía experimental como método, y los últimos escritos religiosos de Boyle, principalmente su Christian Virtuoso, obra publicada en 1690, cerca de su muert

Una ciencia degentlemen: Ciencia experimental y códigos caballerescos en la Inglaterra del siglo XVII

The Social History of Truth, la última obra de Steven Shapín, en ciertos puntos clave de su desarrollo, tiende a mostrar cómo la ciencia experimental propia de los orígenes de la Royal Society es una encarnación de los códigos y convenciones culturales propios de la sociedad caballeresca de la Inglaterra de la Restauración

Principios filosóficos e hipótesis fisicas en Descartes

Ciertas afirmaciones de Descartes en párrafos programáticos de su obra han conducido a interpretar su filosofía de la ciencia como una filosofía racionalista y deductivista. Su comprensión de lo que es un conocimiento estructurado idealmente lo lleva a usar expresiones como "deducción", "axiomas", "fundamentos últimos", entre otros. En el Discurso del método, la enunciación de la regla de claridad y distinción puede ser interpretada, según el contexto, como el criterio para aceptar evidencias de tipo matemático. Y desde este criterio matemático de "claridad y distinción", las otras reglas nos parecerían superfluas

GALEX measurements of the Big Blue Bump as a tool to study bolometric corrections in AGNs

Active Galactic Nuclei emit over the entire electromagnetic spectrum with the peak of the accretion disk emission in the far-UV, a wavelength range historically difficult to investigate. We use here the GALEX (Galaxy Evolution Explorer) Near-UV and Far-UV measurements (complemented with optical data from Sloan Digital Sky Survey (SDSS) and XMM-Newton X-ray spectra) of a sample of 83 X-ray selected type 1 AGN extracted from the XMM-Newton Bright Serendipitous Survey to study their spectral energy distribution (SED) in the optical, Near and Far-UV and X-ray energy bands. We have constrained the luminosity of the accretion disk emission component and calculated the hard X-ray bolometric corrections for a significant sample of AGN spanning a large range in properties (z, L(x)).Comment: 2 pages, 2 figures, To appear in refereed Proceedings of "X-ray Astronomy 2009: Present Status, Multi-Wavelength Approach and Future Perspectives", Bologna, Italy, September 7-11, 2009, AIP, eds. A. Comastri, M. Cappi, and L. Angelin