The Growth-Volatility Relationship: New Evidence Based on Stochastic Volatility in Mean Models

This paper models the relationship between growth and volatility for G7 economies in the time period 1960-2009. It delivers for the first time estimates of this relationship based on a logarithm variant of stochastic volatility in mean (SV-M) models. The relationship appears significantly positive in Germany and Italy, but insignificant in other countries. We also show that output volatility has increased in all countries since the beginning of the financial crisis, which illustrates the end of the great moderation. For comparison, the paper also delivers estimates based on a logarithm variant of GARCH in mean (log-GARCH-M) models, the class of time series models previously used in the literature to estimate the growth-volatility relationship. We show that SV-M models deliver results preferable to those of log-GARCH-M models, despite the high computational cost of their estimation. SV-M models fit generally better data than log-GARCH-M ones. As their residuals do not violate distribution assumptions, they do not deliver dubious conclusions concerning the significance of the relationship, which is the case of the log-GARCH-model for France, the UK and the US. Finally, SV-M models suggest a positive impact of unexpected volatility on output growth, which is not taken into account by log-GARCH-M models.Growth, Volatility, Sequential Monte-Carlo Methods.

The growth and feeding of the Bulwer's Petrel (Bulweria bulwerii) chicks on Selvagem Grande (30º09'N, 15º52'W)

La croissance pondérale et staturale des poussins de Pétrels de Bulwer, Bulweria bulwerii, de Selvagem Grande (30º09’N, 15°52’W) ne diffère en rien de ce qui est habituel chez les Procellariidés. A partir d’un poids à la naissance un peu inférieur au poids de l’oeuf. Une croissance rapide puis ralentie amène les poussins à un poids maximum supérieur au poids de l’adulte. Par la suite, le poids corporel s’abaisse et, à l’envol, ii est un peu inférieur à celui des adultes. La croissance de l’aile, lente avant la pousse des rémiges, puis rapide. Ne s’achève qu’au moment de l’envol. La croissance du culmen et celle du tarse, d’abord rapides puis ralenties s’achèvent respectivement aux environs des deux-tiers et de la moitié du séjour au nid des poussins. La fréquence des repas est à peu près constante pendant toute la période d’accroissement pondéral. Il est probable qu’elle diminue par la suite. Le poids du repas augmente rapidement pendant la première décade de la vie, puis diminue très lentement. Dans ces conditions, la quantité de nourriture consommée quotidiennement augmente pendant la première décade, reste à peu près constante pendant les trois suivantes, puis décroit. Au total, un poussin aura consommé au cours de sa croissance un peu plus de 0,5 kg de nourriture, dont une partie sous forme d’huile stomacale, ce qui semble correspondre à un prélèvement en mer de 1,5 kg, soit environ 17% de la consommation familiale pendant la même période.ABSTRACT: The growth of the chicks of the Bulwer’s Petrel, Bulweria bulwerii, on Selvagem Grande (30º09’N, 15°52’W) shows no differences with what is usual among Procellariidae. The weight at birth is slightly lower than that of the egg. The subsequent increase, rapid at the beginning, slows down, and a maximum weight higher than the adult weight is reached. Later on the body weight lowers and, at fledging, is slightly lower than that of the adult. The wing grows slowly before the appearance of the remiges, then rapidly, and stops at fledging. The growth of the culmen and tarsus, rapid at first, slows down and stops respectively at the two thirds and at half of the chick sojourn on the nest. The feeding frequency, is almost constant during the period of weight gain, and probably lessens afterwards. In these conditions the amount of food eaten daily increases during the first decade of life, remains constant during the following three, and lessens afterwords. On the whole, a chick eats during its growth a little more than 0.5 kg of food, part of which as stomach oil, which seems to correspond to a catch of 1.5 kg, or about 17% of the family intake during the same period

Le travail de proximité auprès des usagers de drogues : comparaisons européennes

A comparative research concerning outreach work with drug users in several european countriesSynthèse d'une recherche comparative sur les différentes formes de travail de proximité auprès des usagers de drogues dans plusieurs pays européens

Le travail de proximité auprès des usagers de drogues en Europe

What is outreach work in different european countries, concerning drug usersRestitution de la synthèse d'une recherche comparative sur les diverses formes de travail de proximité auprès des usagers de drogues dans différents pays européen

Laboratory studies on a spherically curved Bragg spectrometer for cosmic X-ray spectroscopy

A spherical array of twenty LiF 200 crystals was built to test the performances of a freestanding, self-focussing spherical crystal cosmic X-ray spectrometer. Measurements presently available show that the size of the image for a point source at infinite distance would be 3 mm (FWHM) along the focalisation axis and 2.1 mm (FWHM) along the dispersion axis. The mosaic spread on individual crystals is less than 0.1 degree. A slightly systematic deviation from the ideal bending (0.1 degree) is observed at the edges of most crystals and this appears to be the major limitation to spectrometer performance

L'élaboration et la mise en oeuvre de l'Accord économique et commercial global entre l'Union européenne et le Canada

Actes de la 3ème séance du séminaire "L'accord économique et commercial global entre l'Union européenne et le Canada. Du dialogue au libre-échange transatlantique", du 17 mai 2013 organisé à Rennes.International audienc

Realization of the purely spatial Einstein-Podolsky-Rosen paradox in full-field images of spontaneous parametric down conversion

We demonstrate Einstein-Podolsky-Rosen (EPR) entanglement by detecting purely spatial quantum correlations in the near and far fields of spontaneous parametric down-conversion generated in a type-2 beta barium borate crystal. Full-field imaging is performed in the photon-counting regime with an electron-multiplying CCD camera. The data are used without any postselection, and we obtain a violation of Heisenberg inequalities with inferred quantities taking into account all the biphoton pairs in both the near and far fields by integration on the entire two-dimensional transverse planes. This ensures a rigorous demonstration of the EPR paradox in its original position momentum form

Heat recovery subsystem and overall system integration of fuel cell on-site integrated energy systems

The best HVAC (heating, ventilating and air conditioning) subsystem to interface with the Engelhard fuel cell system for application in commercial buildings was determined. To accomplish this objective, the effects of several system and site specific parameters on the economic feasibility of fuel cell/HVAC systems were investigated. An energy flow diagram of a fuel cell/HVAC system is shown. The fuel cell system provides electricity for an electric water chiller and for domestic electric needs. Supplemental electricity is purchased from the utility if needed. An excess of electricity generated by the fuel cell system can be sold to the utility. The fuel cell system also provides thermal energy which can be used for absorption cooling, space heating and domestic hot water. Thermal storage can be incorporated into the system. Thermal energy is also provided by an auxiliary boiler if needed to supplement the fuel cell system output. Fuel cell/HVAC systems were analyzed with the TRACE computer program

Domain wall motion in thin ferromagnetic nanotubes: Analytic results

Dynamics of magnetization domain walls (DWs) in thin ferromagnetic nanotubes subject to weak longitudinal external fields is addressed analytically in the regimes of strong and weak penalization. Exact solutions for the DW profiles and formulas for the DW propagation velocity are derived in both regimes. In particular, the DW speed is shown to depend nonlinearly on the nanotube radius