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Does holding elections during a Covid-19 pandemic put the lives of politicians at risk?
No full textInternational audienceWe estimate the impact of French town hall elections held in mid-March 2020 on the mortality of 163,000 male candidates aged above 60. Their excess mortality during March and April was similar to the general population. We compare candidates in cities with two candidate lists to those in cities with only one list, as elections are more intense in contacts in the former group. We also use a regression discontinuity design and investigate mortality in 2020 depending on how candidates fared in the 2014 election. We cannot detect any causal effect of active participation in the 2020 elections on mortality
Pollution accumulation and abatement policies in two supply chains under vertical and horizontal competition and strategy types
No full textInternational audienc
COVID-19 mortality and health expenditures across European countries: The positive correlation puzzle
No full textThe positive correlation between health share expenditures and COVID-19 case fatalities in a cross-section of 31 European countries is puzzling. The positive relationships is also detected in weighted OLS and IV models that control for many usual suspects of the COVID-19 mortality: (1) health indicators (personal risk factors, medical resources), (2) virus ease of circulation, (3) macroeconomic variables related to the economic development and social orientation of the country. COVID-19 case fatalities are lower in countries with significant resources dedicated to health care (hospital beds and medical doctors); the contribution of virus circulation factors is less significant. Policy implications follow
Une perspective néo-Carnegie et Pragmatiste sur l’Incertitude en Management
No full textIn this report, I explore how to construct managerial “theories of action”, mixing both pragmatic and neo-Carnegie approaches. My research program derives from a performativity assumption to discover managerial theory that can be enacted by human actors in field conditions. This assumption responds to an advocacy for extending the jurisdiction of management scholarship: beyond classical positive theory of management phenomena, I am interested in the study of normative theories and the elaboration of constructive method of knowledge that fit to the logic of our object of study, the manager. My initial studies explore sources of managerial uncertainties, in particular variability effects in various substantive fields such as team diversity, resources-based view, and leadership. I identified various conceptual sources of uncertainties related to variability, such as nuancing effects on outcomes (average vs. extreme) or stochasticity deriving from unidentified moderators. My current research relates the uncertainty in establishing a theory of action to actors behaving inside managerial paradigms. I study how paradigms capture field-specific logics (in leadership or entrepreneurship) or as they reflect adaptiveness by resulting of heuristical systems evolutions. I intend to explore the design of managerial paradigms by identifying their properties—sometimes paradoxical—compared to classical positive science or pedagogy. My approach to research is mostly conceptual. It draws heavily from analogies with other scientific fields and sometimes edges towards epistemology while keeping a tight pragmatic agenda anchored in my past managerial experience. Although my studies rarely focus on the actual and definite empirical validation, they naturally lead to new method developments.Dans ce rapport, j’explore comment construire une « théorie de l’action » de la pratique managériale, en mêlant des approches pragmatiques et néo-Carnegie. Mon programme de recherche découle d’un présupposé de performativité, à savoir d’une curiosité à définir une théorie managériale en ce qu’elle peut être mise en œuvre par l’acteur sur le terrain. Ceci milite pour étendre la recherche en gestion au-delà de la théorie positive en gestion, vers l’étude de théories normatives et l’élaboration de méthode constructive pour produire des savoirs dimensionnés à notre objet d’étude, le manager. Mes premières études explorent les sources d’incertitudes managériales, en particulier les effets de variabilité dans divers domaines tels que la diversité des équipes, les ressources et le leadership. J’y identifiais diverses sources conceptuelles d’incertitudes liées à la variabilité, telles que des effets différentiels sur la performance (moyenne vs extrême) ou de la stochasticité qui dériverait de modérateur non identifié. Ma recherche actuelle relie l’incertitude à déterminer une théorie de l’action au fait que l’acteur ne peut agir que selon des paradigmes managériaux. J’étudie les paradigmes tels qu’ils cristallisent des logiques contextuelles spécifiques (en leadership ou entrepreneuriat) ou qu’ils recèlent une adaptation par évolution de systèmes d’heuristiques. J’ai l’intention d’explorer la conception de paradigmes managériaux en formalisant leurs propriétés — parfois paradoxales — par rapport à la science pure ou à la pédagogie positive classique. Mon approche de la recherche est principalement conceptuelle. Elle s’appuie sur des analogies avec d’autres domaines scientifiques et se rapproche parfois de l’épistémologie tout en gardant un agenda pragmatique ancré dans mon expérience managériale passée. Si mes études se focalisent peu sur la validation empirique, elles mènent souvent à des innovations méthodologiques
LSTM Response Models for Direct Marketing Analytics: Replacing Feature Engineering with Deep Learning
No full textInternational audienc
L'enseignement et la formation dans la transition écologique et sociétale
No full textInternational audienc
Prescription des mesures adjuvantes aux corticothérapies systémiques prolongées en fonction de la spécialité du prescripteur
No full textInternational audienceVitiligo is the most common depigmenting disorder affecting 0.1%-2% of the population worldwide. The characteristic white patches result from the selective loss of melanocytes. Sustained recent efforts have resulted in a detailed understanding of the genetic architecture of vitiligo. About 80% of vitiligo risk is attributable to genetic factors; and the rest (20%) is attributable to the environment. Over the past decade, substantial progress has been made in our understanding of the pathogenesis of vitiligo which is now clearly classified as an autoimmune disease. Melanocytes from patients with vitiligo are more susceptible to oxidative stress which begets the release of exosomes and inflammatory cytokines that will lead to activation of the innate immune response and subsequently to adaptive immune response through activation of autoreactive cytotoxic CD8+ T cells. These produce interferon-γ (IFN-γ) which promotes disease progression through IFN-γ-induced chemokine secretion from surrounding keratinocytes to further recruit T cells to the skin through a positive feedback loop. CD8 tissue-resident memory T cells are in turn responsible for long-term maintenance and potential relapse of vitiligo in human patients through cytokine-mediated recruitment of T cells from the circulation. This review summarizes the current knowledge on vitiligo and attempt to give an overview of the future in vitiligo treatment
Gouvernance d’entreprise à l’aune des AG 2021 : démocratie actionnariale, politique financière et diversité des conseils – Trois questions majeures
No full textThe Covid-19 health crisis has roughly hit companies, which have had to adapt, react, and adapt new practices while maintaining their short and long-term goals. During Annual General Assemblies, especially since these were largely held behind closed doors, the challenge of maintaining good exchanges and an acceptable level of shareholder democracy, if not perfect, was a major task that seemed to us have to draw our attention. The challenge that was not met in the same way, there is a gap between some of them who made efforts and others. Beyond the formal conditions,items discussed in GA were impacted by this exceptional situation: the arise of ethical imperative and the current economic situation evolves, such as the health environment, drove boards of directors to index their dividend and earnings strategies on these new demands. Moreover, these requirements switched on governance itself, mainly on claims about more diversity on boards as executive or non-executive. For many items, Covid has been a revealer or an accelerator and questions are still there.It is within this framework that we sought to analyze answers of companies to three major questions: the conditions of shareholder democracy, the evolution of financial governance decisions and ESG criteria and the diversity and quality of the functioning of boards. Using various academic sources, statistical elements but also company reports, their declarations, viewing of the GA.The scope corresponds to twelve companies listed on the CAC40La crise sanitaire de la Covid-19 a durement frappé les entreprises qui ont dû s’adapter, réagir, adapter de nouvelles pratiques tout en maintenant leurs objectifs de court et long terme. Lors des Assemblées générales, tout particulièrement puisque celles-ci se sont très largement tenues à huis-clos, le défi de la bonne tenue des échanges et d’un niveau de démocratie actionnariale acceptable sinon parfait a constitué un défi majeur prioritaire qui nous a semblé devoir attirer notre attention car le défi que n’a pas été relevé de la même manière, certaines faisant preuve de davantage d’efforts que d’autres. Au-delà des conditions formelles, les sujets abordés en AG eux même ont été impactés par cette situation exceptionnelle et pour certains durablement.On relèvera entre autres la montée d’un impératif éthique à l’aune de la conjoncture économique, et de la crise sanitaire qui ont amené les directions à indexer leurs politiques de dividendes et de rémunérations des dirigeants. Le champ de la gouvernance elle-même a été impacté interrogeant la composition des instances de gouvernement des sociétés cotées mais aussi la qualité de leur fonctionnement : l’équipe dirigeante devait réagir à une situation d’exception, à des risques nouveaux et d’autres aggravés et tous ont bien saisi que le retour au business as usual n’était pas une option.C’est dans ce cadre que nous avons cherché à analyser en mode les réponses d’entreprises à trois questions majeures en 2020 et 2021. A l’aide dediverses sources académiques, d’éléments statistiques mais aussi dans ce domaine qui demeure pratique les rapports d’entreprise, leurs déclarations et le visionnage des AG 2020 et 2021, ont été mises en évidence des tendances sur ces trois problématiques: les conditions de la démocratie actionnariale, l’évolution des décisions de gouvernance financière dont les critères ESG, enfin la diversité et la qualité du fonctionnement des conseils.Le périmètre correspond à douze sociétés cotées du CAC40
Multi-Normex Distributions for the Sum of Random Vectors. Rates of Convergence
No full textWe build a sharp approximation of the whole distribution of the sum of iid heavy-tailed random vectors, combining mean and extreme behaviors. It extends the so-called 'normex' approach from a univariate to a multivariate framework. We propose two possible multinormex distributions, named d-Normex and MRV-Normex. Both rely on the Gaussian distribution for describing the mean behavior, via the CLT, while the difference between the two versions comes from using the exact distribution or the EV theorem for the maximum. The main theorems provide the rate of convergence for each version of the multi-normex distributions towards the distribution of the sum, assuming second order regular variation property for the norm of the parent random vector when considering the MRV-normex case. Numerical illustrations and comparisons are proposed with various dependence structures on the parent random vector, using QQ-plots based on geometrical quantiles