Reprise économique dans les pays post-communistes: application d'un modèle de durée.

After the political collapse of the former communist area, the Central and Eastern European countries, as well as the Former Soviet Union Republics have all experienced a reduction in GDP. At present, some of them have achieved macroeconomic stabilisation and economic revival, while others fail to curb the recession. This paper sheds light on the main factors responsible for this heterogeneity among the post-communist transition countries, thanks to an econometric analysis of a duration model. The estimated variable is the number of years spent in negative growth by each country, since the beginning of transition. The main results are that even if initial conditions played a significant role, the stabilisation, liberalisation and restructuration policies and the speed of their enforcement, had been the essential factors to economic revival.duration model, growth, Transition countries

Analyse des divergences de chômage entre les pays en transition post-communistes

The economic transition in post-communist countries generated a new phenomenon: open unemployment. Since the beginning of the reforms, the official unemployment rates have been very high in the CEECs (Central and Eastern European Countries), compared to the NIS (New Independent States from the Former Soviet Union), where they have stayed at a rate lower than 6%. This article analyses the macro-economic factors responsible for such a divergence in official unemployment rates. The study consist in an econometric estimation of unemployment rates, using panel data on 1991/1992-1996. The first result is that the significant variables are different in the CEECs and in the FSU. In particular, a Phillips curve is rejected in both of groups, as the Okun’s law is valid in the CEECs, but not in the FSU. Moreover, the impact of the reforms is not clear-cut in the CEECS, and is not significant in the FSU. Therefore, the idea that the liberalisations generate unemployment is not comforted by the results of this paper.

Mind the Break! Accounting for Changing Patterns of Growth during Transition

We argue that econometric analyses based on transition countries’ data can be vulnerable to structural breaks across time and/or countries. We demonstrate this argument by identifying structural breaks in growth regressions estimated with data for 25 countries and 16 years. Our method allows identification of structural breaks at a-priori unknown points in space or time. The only prior assumption is that breaks occur in relation to progress in implementing market-oriented reforms. We find robust evidence that the pattern of growth in transition has changed at least two times, yielding thus three different models of growth associated with different stages of reform. The speed with which individual countries progress through these stages differs considerably.growth, Reform, structural breaks, transition

L'ozone en Franche-Comté

Depuis près de 20 ans, l'ozone apparaît fréquemment à la une de nos quotidiens : " trou d'ozone " dans la stratosphère, trop d'ozone dans les basses couches de l'atmosphère... Ces problèmes méritent que l'on s'y intéresse car l'ozone est, à bien des titres, un composant important de la physico-chimie et de la qualité de l'air. Avant de nous pencher sur la situation en Franche-Comté, il nous est apparu souhaitable de présenter un court récapitulatif sur le sujet

Should we stay or should we go? Irregular migration and duration of stay: the case of Moldovan migrants

This paper analyses the link between irregular migration and duration of stay. Using household and regional development data from Moldova and running a duration model, we find that duration of migration is longer for illegal migrants than legal migrants. Further investigation demonstrates that this effect is driven by significantly higher migration costs. From a policy perspective, our findings on irregular migration are highly relevant since they question the outcome of restrictive migration policies. This paper, like an increasing number of migration literature papers converging on the same conclusions, contributes further arguments for redefining migration policy.International migration; Duration model; Irregular migration; Moldova

A simple and effective method for quantifying spatial anisotropy of time series of precipitation fields

The spatial shape of a precipitation event has an important role in determining the catchment's hydrological response to a storm. To be able to generate stochastic design storms with a realistic spatial structure, the anisotropy of the storm has to be quantified. In this paper, a method is proposed to estimate the anisotropy of precipitation fields, using the concept of linear Generalized Scale Invariance (GSI). The proposed method is based on identifying the values of GSI parameters that best describe isolines of constant power on the two-dimensional power spectrum of the fields. The method is evaluated using two sets of simulated fields with known anisotropy and a measured precipitation event with an unknown anisotropy from Brisbane, Australia. It is capable of accurately estimating the anisotropy parameters of simulated nonzero fields, whereas introducing the rain-no rain intermittency alters the power spectra of the fields and slightly reduces the accuracy of the parameter estimates. The parameters estimated for the measured event correspond well with the visual observations on the spatial structure of the fields. The method requires minimum amount of decision making and user interaction, making it suitable for analyzing anisotropy of storm events consisting of long time series of fields with a changing spatial structure.Peer reviewe

Climatology of banded precipitation over the contiguous United States

A climatology of banded-precipitation features over the contiguous United States from 2003–2014 is constructed. A band is defined as a precipitation feature with a major axis of 100 km or greater and a ratio of major axis length to minor axis length (hereafter, aspect ratio) of 3:1 or greater. By applying an automated feature-based detection algorithm to composite radar imagery, a database of 48,916,844 precipitation features is created, of which 7,213,505 (14.8%) are bands. This algorithm produces the first climatology of precipitation bands over the contiguous United States. Banded precipitation occurrence is broadly similar to total precipitation occurrence, with a maximum of 175 hours of banded precipitation annually over the Ohio River Valley. In the warm season, there is a strong diurnal signature associated with convective storm development for both precipitation feature area and total area covered by precipitation, but little diurnal signature in aspect ratio. A strong west-east gradient in both precipitation occurrence and banded precipitation occurrence exist, as areas west of the Rockies receive less frequent precipitation, which is much less likely to be banded. East of the Rockies, precipitation features are banded 30% of the time, versus 10–15% west of the Rockies. Areas downwind of the Great Lakes show prominent late autumn and winter maxima in banded precipitation associated with lake-effect snowbands. Local maxima of banded precipitation percentage occur in the Dakotas and east of the Colorado Rockies during winter. Although banded-precipitation features comprise only 14.8% of all precipitation features, they contribute 21.9% of the annual precipitation occurrence over the contiguous United States

Calcul d'un spectre synthétique d'absorption à basse résolution pour un mélange CO2-CO-gaz neutre à haute température

L'absorptivité monochromatique, avec une résolution de 1 à 10 cm-1 , d'un mélange de gaz purs, contenant CO2, un diatomique hétéronucléaire (CO...) et éventuellement un gaz transparent dans l'infrarouge, est calculée à partir de données spectroscopiques récentes. Les spectres d'absorption, obtenus par cette méthode, sont en bon accord avec des spectres expérimentaux disponibles dans la bibliographie et correspondant à diverses longueurs de la colonne et à des valeurs de la pression totale et de la température s'étendant respectivement de 104 à 106 Pa et de 800 à 1 500 K