Publications

Résumé In this paper, we study the impact of oil price returns on sovereign Credit Default Swaps (CDS) spreads for two major oil producers, Russia and Venezuela. Using daily spreads from 2008 to 2015 through a Time Varying Transition Probabilities Markov Switching model, our results show that crude oil price and its volatility are critical determinants of their sovereign debt. We highlight some differences between the two countries, depending on the state of the economy. Moreover, global and local factors play a major role in the determination of sovereign CDS spreads.
Mots clés Russia, Venezuela, Time series modeling, Markov-switching, Sovereign Credit Default Swaps, Oil prices
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Résumé Introduction Les technologies de l’information et de la communication ont permis la naissance du web 2.0, caractérisé par la mise en place et l’utilisation de nouveaux outils collaboratifs de communication tels que les blogs, les wikis, les fils RSS et les réseaux sociaux. En s’appropriant ces outils, une médecine participative basée sur le partage d’informations et d’expériences entre professionnels, patients et tout acteur de la santé s’est développée. Depuis juin 2012, une communauté médicale échange sur Twitter avec le hashtag #DocTocToc et contribue à la naissance de la e-santé sur ce réseau social. L’objectif de cette étude est d’analyser les principales thématiques des demandes effectuées via le hashtag #DocTocToc par les médecins généralistes entre juin 2012 et mars 2017. Méthodes Une collecte de données par une méthode de « web scraping » a permis de constituer un corpus de tweets dont les auteurs ont été identifiés manuellement afin de procéder à un échantillonnage, de façon à ne conserver que les tweets émis par les médecins généralistes. Une étape de prétraitement a permis de transformer les formes potentiellement non reconnues par les logiciels de traitement du langage naturel. Le corpus a été appréhendé à l’aide de deux approches : une approche lexicale via le logiciel Iramuteq® et une indexation terminologique par l’extracteur de concepts multi-terminologiques (ECMT) du Catalogue et index des sites médicaux francophones (CISMeF). Résultats Sur les 12 716 tweets recueillis, 7366 étaient rédigés par des médecins généralistes et ont été analysés. L’approche lexicale détermine deux grands mondes lexicaux représentés sous forme de dendrogramme, l’un en lien avec les demandes médico administratives relatives à la gestion du cabinet et à la prise en charge sociale du patient, l’autre en lien avec les demandes d’ordre purement médicales. La méthode d’indexation terminologique met en évidence les spécialités médicales pourvoyeuses de demandes de télé-expertise : gynécologie, neurologie, infectiologie, pédiatrie, cardiologie, dermatologie ; et permet de les croiser avec l’objectif de la demande : diagnostic, thérapeutique. Conclusion Sur Twitter®, le hashtag #DocTocToc est utilisé par les médecins généralistes comme un espace de partage informel d’informations en matière de santé mais aussi de gestion de problèmes administratifs et sociaux. Le DocsTocToc se présente comme un groupe d’échange de pratique à grande échelle ou le médecin compte sur l’avis de ses pairs.(Fig. 1)
Mots clés Text mining, Twitter, E-santé, Communication, Big data
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Résumé We develop a model of cross-border acquisitions in which the foreign acquirer's ownership choice reflects a trade-off between easing the target's credit constraints and the costs of operating in an environment with weak institutions. Data on domestic and foreign acquisitions in emerging markets over the period 1990–2007 support the model predictions. The share of full foreign acquisitions is higher in sectors more reliant on external finance, in countries with lower financial development, and in countries with higher institutional quality. Sectoral external finance dependence accentuates the effect of country-level financial development and institutional quality. By contrast, the level of foreign ownership in partial acquisitions is insensitive to institutional factors and depends weakly on financial factors.
Mots clés Institutional quality, Financial development, Mergers and acquisitions, Foreign ownership, Foreign direct investment
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Résumé As it is documented, households’ investment in their own education (human capital) is negatively related to the number of children individuals will have and requires some loans to be financed. We show that this contributes to explain episodes of bubbles associated to higher growth rates. This conclusion is obtained in an overlapping generations model where agents choose to invest in their own education and decide their number of children. A bubble is a liquid asset that can be used to finance either education or the cost of rearing children. The time cost of rearing children plays a key role in the analysis. If the time cost per child is sufficiently high, households have only a small number of children. Then, the bubble has a crowding-in effect because it is used to provide loans to finance investments in education. On the contrary, if the time cost per child is low enough, households have a large number of children. Then, the bubble is mainly used to finance the total cost of rearing children and has a crowding-out effect on investment. Therefore, the new mechanism we highlight shows that a bubble enhances growth if the economy is characterized by a high rearing time cost per child.
Mots clés Human capital, Fertility, Sustained growth, Bubble
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Résumé ICT components, such as microprocessors, may be embodied in other capital goods not recorded as ICT in National Accounts. We name ‘indirect ICT investment’ the value of embodied ICT components in non-ICT investment. The paper provides estimates of ‘indirect ICT investment’ based on detailed and unpublished Supply-Use tables (SUT) in 12 OECD countries: Australia, Belgium, Canada, Chile, Czech Republic, Denmark, France, Germany, Japan, Israel, Mexico, New Zealand, the United Kingdom, and the United States.Our main finding is that ICT investment appears significantly higher when considering its indirect component, the average increase being about 35%. The inclusion of indirect ICT investment, excluding software (for which firms’ expenditures are difficult to measure), changes significantly the relative position of countries with respect to the ICT intensity of their investments. The inclusion of software further increases indirect ICT investment but the increase is smaller (in percentage) than without this inclusion. A final result, but concerning only three countries, it that the diagnosis of a stabilisation, or even a decrease, of ICT investment in percentage of GDP or of total investment, observed from the beginning of the century, is not modified if we take into account the indirect ICT investment.
Mots clés Technology, ICT, Investment
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Résumé Competition between two-sided platforms is shaped by the possibility of multihoming (i.e., some users joining both platforms). If initially both sides singlehome, each platform provides users on one side exclusive access to its users on the other side. If then one side multihomes, platforms compete on the singlehoming side and exert monopoly power on the multihoming side. This paper explores the allocative effects of such a change from single- to multihoming. Our results challenge the conventional wisdom, according to which the possibility of multihoming hurts the side that can multihome, while benefiting the other side. This in not always true, as the opposite may happen or both sides may benefit.
Mots clés Multihoming, Competitive bottleneck, Platform competition, Two-sided markets, Network effects
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Résumé OBJECTIVES: This study assesses the change in premature mortality and in morbidity under the scenario of meeting the World Health Organization (WHO) global targets for non-communicable disease (NCD) risk factors (RFs) by 2025 in France. It also estimates medical expenditure savings because of the reduction of NCD burden. STUDY DESIGN: A microsimulation model is used to predict the future health and economic outcomes in France. METHODS: A 'RF targets' scenario, assuming the achievement of the six targets on RFs by 2025, is compared to a counterfactual scenario with respect to disability-adjusted life years and healthcare costs differences. RESULTS: The achievement of the RFs targets by 2025 would save about 25,300 (and 75,500) life years in good health in the population aged 25-64 (respectively 65+) years on average every year and would help to reduce healthcare costs by about €660 million on average per year, which represents 0.35% of the current annual healthcare spending in France. Such a reduction in RFs (net of the natural decreasing trend in mortality) would contribute to achieving about half of the 2030 NCD premature mortality target in France. CONCLUSIONS: The achievement of the RF targets would lead France to save life years and life years in good health in both working-age and retired people and would modestly reduce healthcare expenditures. To achieve RFs targets and to curb the growing burden of NCDs, France has to strengthen existing and implement new policy interventions.
Mots clés Projection, Obesity, Non-communicable diseases, Smoking, Alcohol, Healthcare expenditure
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Résumé Digital information, particularly for online newsgathering and reporting, is an industry fraught with uncertainty and rapid innovation. Digital Information Ecosystems: Smart Press crosses academic knowledge with research by media groups to understand this evolution and analyze the future of the sector, including the imminent employment of bots and artificial intelligence. The book adopts an original and multidisciplinary approach to this topic: combining the science of media economics with the experience of a practicing journalist of a major daily newspaper. The result is an essential guide to the opportunities of the media to respond to a changing global digital landscape. Independent news reporting is vital in the contemporary democracy; the media must itself become a new smart press.
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Résumé Background: GPs are confronted with therapeutic dilemmas in treating patients with multimorbidity and/or polypharmacy when unfavourable medication risk–benefit ratios (RBRs) conflict with patients’ demands. Aim: To understand GPs’ attitudes about prescribing and/or deprescribing medicines for patients with multimorbidity and/or polypharmacy, and factors associated with their decisions. Design and setting: Cross-sectional survey in 2016 among a national panel of 1266 randomly selected GPs in private practice in France. Method: GPs’ opinions and attitudes were explored using a standardised questionnaire including a case vignette about a female treated for multiple somatic diseases, sleeping disorders, and chronic pain. Participants were randomly assigned one of eight versions of this case vignette, varying by patient age, socioprofessional status, and stroke history. Backward selection was used to identify factors associated with GPs’ decisions about drugs they considered inappropriate. Results: Nearly all (91.4%) responders felt comfortable or fairly comfortable deprescribing inappropriate medications, but only 34.7% decided to do so often or very often. In the clinical vignette, most GPs chose to discontinue symptomatic medications (for example, benzodiazepine, paracetamol/tramadol) because of unfavourable RBRs. When patients asked for ketoprofen for persistent sciatica, 94.1% considered this prescription risky, but 25.6% would prescribe it. They were less likely to prescribe it to older patients (adjusted odds ratio [AOR] 0.48, 95% confidence interval [CI] = 0.36 to 0.63), or those with a stroke history (AOR 0.55, 95% CI = 0.42 to 0.72). Conclusion: In therapeutic dilemmas, some GPs choose to prioritise patients’ requests over iatrogenic risks. GPs need pragmatic implementation tools for handling therapeutic dilemmas, and to improve their skills in medication management and patient engagement in such situations.
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Résumé On many two-sided platforms, users on one side not only care about user participation and usage levels on the other side, but they also care about participation and usage of fellow users on the same side. Most prominent is the degree of seller competition on a platform catering to buyers and sellers. In this paper, we address how seller competition affects platform pricing, product variety, and the number of platforms that carry trade.
Mots clés Two-sided markets, Pricing, Platform competition, Network effects, Intermediation, Imperfect competition
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