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International audience; The study analyses unintentional home and leisure injuries (HLIs) for the French senior population using data from the 2012 wave of the French health, health care and insurance survey. The results of our logit models reveal that health status, age, and risky attitudes are the main characteristics associated with HLIs for older people. When the severity of injuries is taken into consideration, the highest exposure to HLIs concerns the oldest seniors, aged 85 years old or older, with deteriorated health. This result is confirmed in the case of severe indoor HLIs, whereas for severe outdoor injuries, the most vulnerable individuals seem to be younger seniors, that is, 75–79 years old. Moreover, our findings suggest that HLIs, and mainly severe home HLIs, generate a short-term influence on a person's health.

The unit value of a commodity that Michio Morishima's method and its variations enable to determine correctly, is the sum of the value of the commodities it contains (inputs) and the quantity of labor required for its production. However, goods are sold at their market production price only when they meet a solvent social need that involves the entire economy with its interconnections between the different industrial sectors. This condition gives full meaning to Marx's fundamental equalities, which derive from the law of value and constitute invariants that apply to the economy as a whole. These equalities are necessary to determine market production prices. We demonstrate that they also enable to solve the transformation problem for a simple reproduction system without fixed capital by starting from Morishima's formalism and returning to a formalism closer to that used by Marx., Comment: 34 pages

The Casas-Alvero conjecture predicts that every univariate polynomial over a field of characteristic zero having a common factor with each of its derivatives $H_i (f )$ is a power of a linear polynomial. One approach to proving the conjecture is to first prove it for polynomials of some small degree $d$, compile a list of bad primes for that degree (namely, those primes p for which the conjecture fails in degree $d$ and characteristic $p$) and then deduce the conjecture for all degrees of the form $dp^\ell$ , $\ell \in \mathbb{N}$, where $p$ is a good prime for $d$. In this paper we calculate certain distinguished monomials appearing in the resultant $R(f, H_i (f ))$. As a corollary, we obtain a (non-exhaustive) list of bad primes for every degree $d \in \mathbb{N} \setminus 0$.

The microcredit literature indicates that progressive lending should reduce default rates but that it may lead to over-indebtedness. In this study, we show that progressive lending may be safe over a range of loan sizes, beyond which a rational borrower would indulge in a strategic default. This range of loan sizes may be dependent on borrower characteristics (risk-taking, self-confidence, productivity, interest rates, subsistence needs) as well as the Microfinance Institution's strategy. Many crowdfunding sites are using artificial intelligence to assess borrower risk through social ratings. We are arguing that production functions of the borrowers also need to be added.

We present a model of worldwide crisis contagion based on the Google matrix analysis of the world trade network obtained from the UN Comtrade database. The fraction of bankrupted countries exhibits an \textit{on-off} phase transition governed by a bankruptcy threshold $\kappa$ related to the trade balance of the countries. For $\kappa>\kappa_c$, the contagion is circumscribed to less than 10\% of the countries, whereas, for $\kappa, Comment: Main article: 19 pages, 9 figures. Supplementary files: 7 pages, 2 figures, 4 tables, 1 video. Datasets, results, supplementary information, and high quality figures available at this http://perso.utinam.cnrs.fr/~lages/datasets/WTNcrisis/

International audience; This paper aims to analyze environmental Total Factor Productivity (TFP) change. Indeed, innovative environmental TFP measures are introduced through convex and non convex environmental production processes. Hence, the impacts of input and output quality change on environmental productivity variation are underscored. In addition, general decomposition of the new ratio- and difference-based environmental TFP measures is proposed. Finally, an empirical example is provided to illustrate these propositions.

In this paper, we consider an equally weighted bipartite matching market with transferability of the utility. We analyze the equilibrium of the market in the case of nearly full matching and in the case of nearly scarce matching. Considering a particular case of full matching with a quadratic specification and Gaussian distributions of the characteristics, we find entirely the analytical expression the optimal matching and of the individual surpluses gained by the partners from the sharing of the joint surplus at the equilibrium. We provide two ways to estimate the model.

International audience; In this paper, we propose a new definition of sustainability that includes dynamics and equity. We propose a theoretical framework that allows finding a fair and sustainable strategy for all stakeholders. More precisely, the framework allows calculating a strategy which ensures that in the long run the interests of all the stakeholders are reconciled. In order to calculate a such a strategy, we model stakeholders and actors as dynamical systems in state-space form. Furthermore, we use robust control and linear matrix inequalities to calculate the desired strategy. We use several simulation scenarios to show the effectiveness of our proposed framework. Response to Reviewers: For a detailed response to reviewer's comments please see the pdf file containing the revised manuscript and our response to reviewers attached to the revised version of our manuscript

Today, all companies in search of performance must be part of a dynamic of transformation and opt for new technologies and new management tools. The social management control, a recent function, is gradually being installed in Moroccan companies to meet the needs of HR management related to the measurement of its performance and the achievement of its objectives. Through an empirical study carried out on 500 companies with a response rate of 18% (90 companies) and by positioning ourselves on a positivist methodological posture, we were able to identify the best HR practices, namely HR Steering, Management of social relations and the best CGS practices, namely the Control of HR Steering, Control of Career Management, Control of the management of social relations, impacting positively and directly the social performance and indirectly the financial performance. Thus, we were able to testify to the positive relationship between social performance and financial performance, and to present the profile of the Moroccan social management controller, in addition to the social management control tools adopted by Moroccan companies., Aujourd’hui, toutes les entreprises en quête de la performance doivent s’inscrire dans une dynamique de transformation et opter pour de nouvelles technologies et de nouveaux outils de gestion. Le contrôle de gestion sociale, fonction récente, s’installe petit à petit dans les entreprises marocaines pour répondre aux besoins de la direction RH liées à la mesure de sa performance et à l’atteinte de ses objectifs. A travers une étude empirique réalisée sur 500 entreprises avec un taux de réponse de 18% (90 entreprises) et en se positionnant sur une posture méthodologique positiviste, nous avons pu dégager les meilleures pratiques RH à savoir le Pilotage RH, Gestion des relations sociales et les meilleures pratiques CGS à savoir le Contrôle du Pilotage RH, Contrôle de la gestion des carrières, Contrôle de la gestion des relations sociales, impactant positivement et directement la performance sociale et indirectement la performance financière. Ainsi, nous étions en mesure de témoigner de la relation positive entre la performance sociale et la performance financière, et de présenter le profil du contrôleur de gestion sociale Marocain, outre les outils de contrôle de gestion sociale adoptées par les entreprises marocaines.

We provide a comprehensive analysis of the two-parameter Beta distributions seen from the perspective of second-order stochastic dominance. By changing its parameters through a bijective mapping, we work with a bounded subset D instead of an unbounded plane. We show that a mean-preserving spread is equivalent to an increase of the variance, which means that higher moments are irrelevant to compare the riskiness of Beta distributions. We then derive the lattice structure induced by second-order stochastic dominance, which is feasible thanks to the topological closure of D. Finally, we consider a standard (expected-utility based) portfolio optimization problem in which its inputs are the parameters of the Beta distribution. We explicitly characterize the subset of D for which the optimal solution consists of investing 100% of the wealth in the risky asset and we provide an exhaustive numerical analysis of this optimal solution through (color-coded) graphs.

International audience; We present a model for research and development (R&D) investment in food innovations based on new plant engineering techniques (NPETs) and traditional hybridization methods. The framework combines uncertain and costly food innovation with consumers' willingness to pay (WTP) for the new food. The framework is applied with elicited WTP of French and US consumers for new improved apples. NPETs may be socially beneficial under full information and when the probability of success under NPETs is relatively high. Otherwise, the traditional hybridization is socially optimal. A probable collapse of conventional apples raises the social desirability of new apples generated by NPETs and traditional hybridization.; Nous présentons un modèle d'investissement en recherche et développement (R&D) dans le domaine alimentaire, en prenant en considération les nouvelles techniques d'ingénierie végétale (NTIV) et les méthodes d'hybridation traditionnelles. Le modèle intègre une innovation alimentaire incertaine et coûteuse, ainsi que les consentements à payer des consommateurs (CAP) pour le nouvel aliment. Ce cadre conceptuel est appliqué au cas de nouvelles pommes se conservant plus longtemps et brunissant moins vite, en prenant en compte les CAP des consommateurs français et américains pour ces nouvelles pommes. Il est montré que les NTIV peuvent être socialement bénéfiques dans un contexte d’information complète, et lorsque la probabilité de succès avec ces NTIV est relativement élevée. Sinon, l'hybridation traditionnelle est socialement optimale. Une menace importante sur la production des pommes conventionnelles augmente la désirabilité sociale de nouvelles pommes générées par les NTIV ou l'hybridation traditionnelle.

International audience; We perform meta-regressions on a single database containing 96 observations of simple ultimatum games and 144 observations of simple dictator games to disentangle the fairness hypothesis based on the degree of economic development of a country. According to the fairness hypothesis, o ers in the two games should not di er if they were motivated by a subject's fairness concerns. Using the di erence across countries between o ers in ultimatum and dictator games, we address the e ect of being exposed to the market mechanism on pure fairness concerns and other-regarding, expectations-driven fairness. Our results show in particular that the lower the level of economic development in a country, the less likely the rejection of the fairness hypothesis.

A principal component analysis based on the generalized Gini correlation index is proposed (Gini PCA). The Gini PCA generalizes the standard PCA based on the variance. It is shown, in the Gaussian case, that the standard PCA is equivalent to the Gini PCA. It is also proven that the dimensionality reduction based on the generalized Gini correlation matrix, that relies on city-block distances, is robust to out-liers. Monte Carlo simulations and an application on cars data (with outliers) show the robustness of the Gini PCA and provide different interpretations of the results compared with the variance PCA.

International audience; How do countries respond to other countries when setting the level of their environmental expenditures? Using data from 1995-2017 on a sample of 28 OECD countries, we examine the nature and extent of strategic interactions in environmental expenditures among OECD countries using a spatial Durbin model including economic and political control variables and both economic and spatial weight matrices reflecting several interaction mechanisms. The results show the existence of significant positive spatial dependence in environmental spending suggesting that OECD countries consider their neighbors' behavior when making policy choices related to environmental expenditures. We also find that the most populous countries or those with high unemployment tend to spend less for environment while countries with a large urban population set higher levels of environmental expenditures. The results are robust to the inclusion of strong cross-sectional dependence under the form of common factors.

We propose a novel approach in the assessment of a random risk variable $X$ by introducing magnitude-propensity risk measures $(m_X,p_X)$. This bivariate measure intends to account for the dual aspect of risk, where the magnitudes $x$ of $X$ tell how hign are the losses incurred, whereas the probabilities $P(X=x)$ reveal how often one has to expect to suffer such losses. The basic idea is to simultaneously quantify both the severity $m_X$ and the propensity $p_X$ of the real-valued risk $X$. This is to be contrasted with traditional univariate risk measures, like VaR or Expected shortfall, which typically conflate both effects. In its simplest form, $(m_X,p_X)$ is obtained by mass transportation in Wasserstein metric of the law $P^X$ of $X$ to a two-points $\{0, m_X\}$ discrete distribution with mass $p_X$ at $m_X$. The approach can also be formulated as a constrained optimal quantization problem. This allows for an informative comparison of risks on both the magnitude and propensity scales. Several examples illustrate the proposed approach.

In this paper, we define stochastic volatility operators in Hilbert space which are analogs to the widely-used SABR model [14] in finite dimensional case. We show the existence of the mild solution and some related regularity properties. Our proof is based on Leray-Schauder fixed point theorem and some priori inequalities on the stochastic operator processes we construct.

International audience; We built a database of two samples of patients surveyed within the same regions in rural China over a time interval of 18 years, and presumed varying demand heterogeneity due to income increase and people aging. We find that while the mean price and distance negative effects on patients choice were present in both time periods, their differences in heterogeneity, which were confirmed with the mixed multinomial logit (MMNL), could have crucial importance in avoiding erroneous policy making based merely on mean price and distance effects. We also find that while both the multinomial logit (MNL) and the MMNL are able to predict price and distance effects with low heterogeneity, only the MMNL appears able to detect the price effect when heterogeneity is high. These findings suggest using caution when interpreting estimation results with the MNL in cases of high heterogeneity.

'Rich get richer' rule comforts previously often chosen actions. What is happening to the evolution of individual inclinations to choose an action when agents do interact ? Interaction tends to homogenize while each individual dynamics tends to reinforce its own position. Interacting stochastic systems of reinforced processes were recently considered in many papers, where the asymptotic behavior was proven to exhibit a.s. synchronization. We consider in this paper models where, even if interaction among agents is present, absence of synchronization may happen due to the choice of an individual non-linear reinforcement. We show how these systems can naturally be considered as models for coordination games, technological or opinion dynamics.

This paper investigates the determinants of firms investment financing constraints. Using an endogenous switching regression model on French Provence-Alpes Côte d'Azur region firms data collected between 2005-2014, we provide a novel evidence of the role of inter-enterprises payment deadlines which are days receivable outstanding and days payable outstanding, as factors determining rms investment nancing constraints. We also show that there is a non-negligible number of firms switching each year either from constrained regime to unconstrained regime or unconstrained regime to constrained one. By developing a model, we highlight the factors determining firms regime change.

National audience; Most integrated models of the covid pandemic have been developed under the assumption that the policy-sensitive reproduction number is certain. The decision to exit from the lockdown has been made in most countries without knowing the reproduction number that would prevail after the deconfinement. In this paper, I explore the role of uncertainty and learning on the optimal dynamic lockdown policy. I limit the analysis to suppression strategies where the SIR dynamics can be approximated by an exponential infection decay. In the absence of uncertainty, the optimal confinement policy is to impose a constant rate of lockdown until the suppression of the virus in the population. I show that introducing uncertainty about the reproduction number of deconfined people reduces the optimal initial rate of confinement.

This report presents the results of an impact analysis of several reform options of the agricultural produce cess in Tanzania. The produce cess is a levy charged by Local Governments Authorities (LGAs) on the value of the marketed agricultural production. This analysis is achieved using a micro-economic model applied to a representative sample of 3134 farm-households spread out over all the country coming from the World Bank-LSMS-ISA surveys. The potential effects of the simulated reform options on land use, production, input use, farm income, LGAs revenues and some food security related indicators are presented and discussed., JRC.D.4-Economics of Agriculture

International audience; Ce texte propose une critique radicale de la décomposition de Oaxaca-Blinder appliquée aux inégalités salariales. Cette méthode décompose un écart salarial entre deux groupes entre une part « expliquée » par les différences de compétences et une part « inexpliquée » appelée effets de la discrimination. On montre ici, en les passant en revue, que des critiques techniques nombreuses minent la prétention de la méthode à pouvoir chiffrer la discrimination. Le problème principal est cependant l'utilisation d'hypothèses contrefactuelles irréalistes. Le texte conclut donc qu'il faut renoncer à chiffrer la discrimination salariale par cette méthode et qu'il est sans doute préférable d'étudier la discrimination par d'autres voies.

In cooperative game theory, the concept of interaction index is an extension of the concept of value, considering interaction among players. In this paper we focus on cardinal-probabilistic interaction indices which are generalizations of the class of semivalues. We provide two types of decompositions. With the first one, a cardinal-probabilistic interaction index for a given coalition equals the difference between its external interaction index (or co-Möbius transfom) and a weighted sum of the individual impact of the remaining players on the interaction index of the considered coalition. The second decomposition, based on the notion of the "decomposer", splits an interaction index into a direct part, the decomposer, which measures the interaction in the coalition considered, and an indirect part, which indicates how all remaining players individually affect the interaction of the coalition considered. We propose alternative characterization of the cardinal-probabilistic interaction indices. We then propose an illustration with a well-known example in Multicriteria Aid for Decisions.

International audience; The impact of housing hazards on health outcomes is becoming a major issue especially given the recent and on-going reviews of energy legislation in many European countries. A large body of epidemiological literature argues that fuel poverty – a frequently debated example of a housing hazard involving low indoor temperatures – is associated with heightened health risks.By using a large scale nationally representative dataset, I seek in this article to delve into this alleged association and uncover a causal relationship between fuel poverty and self-assessed health. Coming from an economics standpoint, I used a panel approach based on an instrumental fixed-effects model which allow me to analyse causality. I used both objective and subjective fuel-poverty indicators.The results show that there is a significant causal relationship between fuel poverty and self-assessed health status. The estimated causality is exacerbated when subjective fuel-poverty indicators are used. The results also show that the negative impact of fuel poverty on health is deferred, meaning that fuel poverty takes time to manifest itself in terms of poor health.In policy terms, this study adds to the debate on investing in housing energy-efficiency schemes to reduce fuel poverty and thereby improve health outcomes. It also lends support to the argument according to which improving housing conditions to curb fuel poverty is a lever for reducing pubic expenditures on health care.

The interest of this paper is to show the effect of the action of the public power over the management of public expenditure on education. Our empirical attempt tries to clarify the direct and indirect effects of the efficiency of the government on the development of public spending for the education sector during the 1984-2018 periods in in the MENA region while using the model of simultaneous equations., L'intérêt de cet article est de montrer l'effet de l'action du pouvoir public sur la gestion des dépenses publiques d'éducation. Notre tentative empirique tente de clarifier les effets directs et indirects de l'efficacité du gouvernement sur le développement des dépenses publiques pour le secteur de l'éducation au cours des périodes 1984-2018 dans la région MENA tout en utilisant le modèle d'équations simultanées.

La capacite de mobilite quotidienne des jeunes, en transport individuel ou collectif, est un facteur determinant de leurs chances d’insertion professionnelle, en particulier pour les jeunes decrocheurs qui ont quitte le systeme scolaire sans acceder a une formation ou a un emploi, et pour qui la faible capacite de deplacement est un obstacle avere a l’insertion professionnelle. Dans ces conditions, comment ameliorer la mobilite de ces jeunes decrocheurs ? Dans cet article, nous presentons les resultats d’une evaluation d’impact par experience controlee de seize dispositifs innovants cibles sur ce public particulier. Portes par des associations locales ou nationales, ces dispositifs ont des contenus varies : diagnostic en matiere de mobilite, formation a la mobilite dans le cadre d’ateliers, apprentissage de modes de transport alternatifs, mise a disposition de deux-roues, aides financieres et accompagnement pour le passage du permis de conduire et pour l’acquisition d’un vehicule. La base de donnees experimentale couvre 275 jeunes suivis entre aout 2015 et decembre 2016. L’evaluation montre qu’une aide a la mobilite ameliore les chances d’acces a une formation et a un emploi. Toutefois, l’intensite des actions joue un role important. A trop faible dose, les aides a la mobilite peuvent meme avoir un effet contre-productif sur l’insertion des jeunes. Pour qu’elles soient efficaces, ces aides gagnent a etre intensives. Codes JEL : C93, J16, J61, J71

This paper develops a discrete-time stochastic endogenous growth model to study the amplification role of fiscal rules. In our model, transitory shocks exert permanent effects on the level of variables in equilibrium (hysteresis), and can be strongly amplified by the public debt adjustment, leading to a procyclical amplification mechanism (the "public debt accelerator"). This procyclical stance depends on the speed of adjustment of the debt-to-GDP ratio under a fixed-fiscal rule. A cold turkey strategy removes the public debt shock, but at the risk of destabilizing other variables, while a gradualist strategy has a stabilization effect, with detrimental consequences in the long-run. Finally, we show that a flexible-fiscal rule helps smooth aggregate variables by limiting the cuts in productive public spending.

International audience; We reexamine some of the classic problems connected with the use of cardinal utility functions in decision theory, and discuss Patrick Suppes' contributions to this field in light of a reinterpretation we propose for these problems. We analytically decompose the doctrine of ordinalism, which only accepts ordinal utility functions, and distinguish between several doctrines of cardinalism, depending on what components of ordinalism they specifically reject. We identify Suppes' doctrine with the major deviation from ordinalism that conceives of utility functions as representing preference differences, while being nonetheless empirically related to choices. We highlight the originality, promises and limits of this choice-based cardinalism.

This study aims to highlight the issues and challenges of innovation in the olive sector in Bejaia province. To do this, we used a methodology based on the Agricultural Innovation Systems approach, built around the neo-Schumpeterian evolutionary theory, as well as different approaches to institutional change. First of all, the Algerian Agricultural Innovation System has been compared to a sample of olive oil exporting countries. In addition, a retrospective analysis focused on agricultural policy and R&D, as well as olive growing in Algeria. Finally, we have carried out a microeconomic statistical analysis to find out about the determinants of innovation in olive farms. The main result from this research is that innovation in olive growing in Bejaia province faces structural constraints inherent in the overall historical evolution of agriculture in Algeria. In addition, it turns out that olive farmers in Bejaia province seem not to take advantage of their interactions with most of knowledge and information institutions and organizations., Ce travail de recherche a pour objet de mettre en évidence les enjeux et les défis en matière d’innovation dans le secteur de l’oléiculture de la wilaya de Béjaïa. A cet effet, nous avons adopté une méthodologie axée sur l’approche des Systèmes d’Innovation Agricole, développée sur la base de la théorie évolutionniste néo-schumpétérienne, ainsi que différentes approches du changement institutionnel. Dans un premier temps, le Système algérien d’Innovation Agricole a fait l’objet d’une analyse comparative par rapport à ceux d’un échantillon de pays exportateurs d’huile d’olive. Par ailleurs, une analyse rétrospective a porté sur la politique et la R&D agricoles, ainsi que sur l’oléiculture en Algérie. Enfin, nous avons effectué une analyse statistique microéconomique afin de mettre en exergue les déterminants de l’innovation dans les exploitations oléicoles. A l’issue de ce travail de recherche, il s’est avéré que l’innovation en oléiculture dans la wilaya de Béjaïa fait face à des contraintes structurelles inhérentes à l’évolution historiques du secteur de l’agriculture en Algérie. Ce travail a également montré que les oléiculteurs de la wilaya de Béjaïa ne profitent guère de leurs interactions avec la plupart des sources institutionnelles de connaissances et d'informations.

This study aims to investigate the relationship between foreign direct investment (FDI) and exports' performance. In fact, the literature review on the subject would not be conclusive, and raises deviations about the contribution of multinational firms in improving export performance. Thus, the analysis is conducted through a dynamic panel data model of 23 developing countries and estimated by SGMM method. Hence, results analysis affirms the existence of a positive relationship between foreign direct investment inflows and exports' performance.

This study aims to highlight the issues and challenges of innovation in the olive sector in Bejaia province. To do this, we used a methodology based on the Agricultural Innovation Systems approach, built around the neo-Schumpeterian evolutionary theory, as well as different approaches to institutional change. First of all, the Algerian Agricultural Innovation System has been compared to a sample of olive oil exporting countries. In addition, a retrospective analysis focused on agricultural policy and R&D, as well as olive growing in Algeria. Finally, we have carried out a microeconomic statistical analysis to find out about the determinants of innovation in olive farms. The main result from this research is that innovation in olive growing in Bejaia province faces structural constraints inherent in the overall historical evolution of agriculture in Algeria. In addition, it turns out that olive farmers in Bejaia province seem not to take advantage of their interactions with most of knowledge and information institutions and organizations., Ce travail de recherche a pour objet de mettre en évidence les enjeux et les défis en matière d’innovation dans le secteur de l’oléiculture de la wilaya de Béjaïa. A cet effet, nous avons adopté une méthodologie axée sur l’approche des Systèmes d’Innovation Agricole, développée sur la base de la théorie évolutionniste néo-schumpétérienne, ainsi que différentes approches du changement institutionnel. Dans un premier temps, le Système algérien d’Innovation Agricole a fait l’objet d’une analyse comparative par rapport à ceux d’un échantillon de pays exportateurs d’huile d’olive. Par ailleurs, une analyse rétrospective a porté sur la politique et la R&D agricoles, ainsi que sur l’oléiculture en Algérie. Enfin, nous avons effectué une analyse statistique microéconomique afin de mettre en exergue les déterminants de l’innovation dans les exploitations oléicoles. A l’issue de ce travail de recherche, il s’est avéré que l’innovation en oléiculture dans la wilaya de Béjaïa fait face à des contraintes structurelles inhérentes à l’évolution historiques du secteur de l’agriculture en Algérie. Ce travail a également montré que les oléiculteurs de la wilaya de Béjaïa ne profitent guère de leurs interactions avec la plupart des sources institutionnelles de connaissances et d'informations.

International audience; Experimental economists increasingly apply econometric techniques to interpret their data, as suggests the emergence of " experimetrics " in the 2000s. Yet statistics remains a minor topic in historical and methodological writings on experimental economics (EE). This article aims to address this lacuna. To do so, we analyze the use of statistical tools in EE from early economics experiments of the 1940s-1950s to the present days. Our narrative is based on qualitative analysis of papers published in early periods and quantitative analysis of papers published in more recent periods. Our results reveal a significant change in EE' statistical methods, namely an evolution from purely descriptive methods to more sophisticated and standardized techniques. We also highlight that, despite the decisive role played by statistics in the way EE estimate the rationality of individuals or markets, statistics are still considered as involving non-methodological issues, i.e., as involving only purely technical issues. Our historical analysis shows that this technical conception was the result of a long-run evolution of the process of scientific legitimization of EE, which allowed experimental economists to escape from psychologist's more reflexive culture toward statistics.

International audience; Common dynamical properties of business cycle fluctuations are studied in a sample of more than 100 countries that represent economic regions from all around the world. We apply the methodology of multivariate singular spectrum analysis (M-SSA) to identify oscillatory modes and to detect whether these modes are shared by clusters of phase- and frequency-locked oscillators. An extension of the M-SSA approach is introduced to help analyze structural changes in the cluster configuration of synchronization. With this novel technique, we are able to identify a common mode of business cycle activity across our sample, and thus point to the existence of a world business cycle. Superimposed on this mode, we further identify several major events that have markedly influenced the landscape of world economic activity in the postwar era.

International audience; This paper analyzes the challenges related to the assessment of co-benefits of climate policies underpinned by the implementation of multi-objective policies which seek synergies between climate policies and other development objectives (poverty alleviation, employment, health etc.). The analysis highlights the increasing interest in co-benefits in the latest 5th IPCC report, in particular by integrated models. Nevertheless, the quantified evaluation of co-benefits is still confronted to several methodological limitations which reduce the scope of co-benefits, particularly at the global level. In a growing context of climate-development approaches in climate negotiations, this article insists on the need to also assess cobenefits of other policies which induce a significant part of GHG emissions. Considering climate policies focused only on Greehouse Gases emissions reduction limits the range of policy instruments to carbon taxation, tradable carbon emissions permits or dedicated mitigation and adaptation funds. This also hinders the integration of climate objectives in non-climate policies. Analyzing impacts of developmentpolicies on Green Gases emissions in the form of co-benefits requires to broaden the range of policy instruments and to take into account other drivers of emissions such as land dynamics. Including these mechanisms in integrated models therefore represents new scientific frontiers for integrated models in the coming years.; Cet article 1 examine les enjeux sous-jacents à l'évaluation des cobénéfices des politiques climatiques dans le cadre de la mise en oeuvre de politiques multi-objectifs, au sein lesquelles des synergies sont recherchées entre la lutte contre le changement climatique et des objectifs de développement (emploi, santé, sortie de la pauvreté, etc.). L'analyse du cinquième rapport du groupe III du GIEC montre en effet un intérêt grandissant dans la littérature pour les évaluations quantifiées des cobénéfices, en particulier à l'aide de modèles numériques intégrés. Néanmoins, l'évaluation quantifiée à une échelle globale des cobénéfices est confrontée à des difficultés d'ordre méthodologique qui expliquent l'écart entre les pratiques des modélisateurs et la vision théorique des économistes qui repose sur l'analyse coûts-bénéfices. L'article revient enfin sur la nécessité d'élargir le champ d'investigation de l'évaluation des cobénéfices aux politiques non climatiques qui déterminent une part importante des émissions de GES, et constituent un des enjeux majeurs des approches intégrées climat-développement qui montent en puissance dans les négociations climat en cours. Abstract – Co-benefits of climate policies: a potential keystone of climate negotiations? This paper analyzes the challenges related to the assessment of co-benefits of climate policies underpinned by the implementation of multi-objective policies which seek synergies between climate policies and other development objectives (poverty alleviation, employment, health etc.). The analysis highlights the increasing interest in co-benefits in the latest 5th IPCC report, in particular by integrated models. Nevertheless, the quantified evaluation of co-benefits is still confronted to several methodological limitations which reduce the scope of co-benefits, particularly at the global level. In a growing context of climate-development approaches in climate negotiations, this article insists on the need to also assess co-benefits of other policies which induce a significant part of GHG emissions. Considering climate policies focused only on Greehouse Gases emissions reduction limits the range of policy instruments to carbon taxation, tradable carbon emissions permits or dedicated mitigation and adaptation funds. This also hinders the integration of climate objectives in non-climate policies. Analyzing impacts of development policies on Green Gases emissions in the form of co-benefits requires to broaden the range of policy instruments and to take into account other drivers of emissions such as land dynamics. Including these mechanisms in integrated models therefore represents new scientific frontiers for integrated models in the coming years.

International audience; By how much does the presence of behavioral uncertainty in an experimental asset market reduce subjects' confidence in their price forecasts? An incentivized interval forecast elicitation method is employed to answer this question. Each market consists of six traders, and the value of dividends is known. Two treatments are considered: six human traders (6H), and one human interacting with five computer traders whose behavior is known (1H5C). We find that while the deviation of the initial price forecasts from fundamental value is smaller in the 1H5C treatment than in the 6H treatment, albeit not statistically significantly, the average confidence regarding the forecasts is not. We further analyze the relationships between subjects' confidence in their forecasts and their trading behavior, as well as their trading performance, in the 6H treatment. While subjects' high confidence in their short-term forecasts shows a negative correlation with their trading performance, high confidence in their long-term forecasts shows a positive correlation with trading performance.

This thesis deals with various issues related to collateral management in the context of centralized trading through central clearing houses. In the first place, we present the notions of cost of capital and funding cost for a bank, placing them in an elementary Black–Scholes framework where the payoff of a standard call is used as the exposure at default of a counterparty. It is assumed that the bank can’t perfectly hedge this call and must face with a funding cost higher than the risk free rate, hence pricing corrections of the FVA and KVA type appear in top of the Black–Scholes price. Then, we look at the different costs that a bank has to face when trading in the CCP context. To this end, we transpose the well-known XVA analysis framework from the bilateral trading world to the central clearing one. The total cost for a member trading through a CCP is thus decomposed into aCVA corresponding to the cost for the member to reimburse its contribution to the guarantee fund in the event of losses due to the defaults of other members, a MVA which is the cost of financing its initial margin and a KVA corresponding to the cost of capital put at risk by the member in the form of its contribution to the guarantee fund. Afterwards, we question the previously used regulatory assumptions, focusing on alternatives in which members would borrow their initial margin to a third party who would post the margin instead of the member himself, and this, in exchange for remuneration. We also consider a method of computing the guarantee fund and its allocation taking into account the risk of the CCP in the sense of fluctuations of its P&L over the following year, as it results from the market risk and the counterparty risk of the members. Finally, we propose the application of multivariate risk measure methodologies for the computation of margins and/or the CCP guarantee fund. We introduce a notionof systemic risk measures in the sense that they are sensitive not only to the marginal risks of the components of a financial system (for example, but not necessarily the positions of the members of a CCP) but also to the dependence of their components., Cette thèse traite de diverses problématiques ayant trait à la gestion du collatéral dans le contexte du trading centralisé au travers des chambres de compensation. Préliminairement, nous présentons les notions de coûts de capital et coût de financement pour une banque, en les replaçant dans un cadre Black–Scholes élémentaire où le payoff d’un call standard tient lieu d’exposition au défaut d’une contrepartie. On suppose que la banque ne couvre qu’imparfaitement ce call et doit faire face à un coût de financement supérieur au taux sans risque, d’où des corrections de pricing de type FVA et KVA par rapport au prix Black–Scholes. Nous nous intéressons ensuite aux coûts auxquels une banque doit faire face lorsqu' elle trade dans le cadre d’une CCP. A cette fin, nous transposons au trading centralisé le cadre d’analyse XVA du trading bilatéral. Le coût total pour un membre de trader au travers d’une CCP est ainsi décomposé en une CVA correspondant au coût pour le membre de renflouer sa contributionau fonds de garantie en cas de pertes consécutives aux défauts d’autres membres, une MVA correspondant au coût de financement de sa marge initiale et une KVA correspondant au coût du capital mis à risque par le membre sous la forme de sa contribution au fonds de garantie. Nous remettons ensuite en cause les hypothèses réglementaires précédemment utilisées, nous intéressant à des alternatives dans lesquelles les membres auraient recours pour leur marge initiale à une tierce partie, qui posterait la marge à la place du membre en échange d’une rémunération.Nous considérons également un mode de calcul du fonds de garantie et de son allocation qui prennent en compte le risque de la chambre au sens des fluctuations de son P&L sur l’année suivante, tel qu’il résulte de la combinaison des risque de marché et des risques de défaut des membres. Enfin, nous proposons l’application de méthodologies de type mesures de risque multivariées pour le calcul des marges et/ou du fonds de garantie des membres. Nous introduisons une notion de mesures de risque systémiques au sens où elles présentent une sensibilité non seulementaux risques marginaux des composantes d’un système financier (par exemple, mais non nécessairement, les positions des membres d’une CCP), mais aussi à leur dépendance.

Document de travail publié ensuite dans un article dans PloS One sous le titre de : "Trust or robustness? An ecological approachto the study of auction and bilateral markets"; Centralized markets are often considered as being more efficient thanbilateral exchanges, based on the fact that information is uniformlyspread among all the agents. However, the influence of trust onthe outcome of decentralized markets has been underlined by manyauthors. We present an empirical study of the distinctive Boulogne-sur-Mer sh market (where both buyers and sellers can choose totrade by either bidding or bargaining), focused on the interactionsamong agents. The approach we adopt derives from the studies ofmutualistic ecosystems, where the agents are of two different types(like in plants - pollinators networks) and the interactions only takeplace between agents of different kind, bringing naturally a benefit for both. In our context, where the two kinds of agents are buyersand sellers, our study shows that their interactions, not only bringthe economic benefits for the directly involved agents, but they alsocontribute to the stability of the market. Our results help to under-stand the surprising coexistence of the two forms of markets in theBoulogne sur Mer sh-market.

The objective of this thesis is to study, first, the effect of the control of corruption on human capital and to identify the consequences of this impact on the component of public spending for education and health and also on the quality of services and their yields while using several methods of estimation and testing the robustness of the equation to estimate. Secondly, we try to empirically explore the impacts of the effectiveness ofthe action of power, as an index of governance quality on economic growth through investment and human capital in our study sample. Finally, we try to show the direct and indirect effects of corruption control via the action of public power on economic development across the sectors of education and health .This work also seeks to clarify how improvement of skills and education levels of human capital through the allocation of public spending on areas of education and health. In addition and in this thesis, we test the complementarity of the important role of the action of the public power and control of corruption that represents an arbitration model in institutional economics while using a model to simultaneous equation for the study areas, MENA and OECD. In total, to explain the relationship between the control of corruption and economic development through the basic social sectors, we must resort to strong econometric synthesis to show that corruption has a social effect and it also has economic and political implications our sample., L'objectif de cette thèse est d'étudier, en premier lieu, l'effet du contrôle de la corruption sur le capital humain et de dégager les conséquences de cet impact sur la composante des dépenses publiques de l‟éducation et de la santé et aussi sur la qualité des services et leurs rendements tout en utilisant plusieurs méthodes d‟estimation et en testant la robustesse de l'équation à estimer. En second lieu, nous tentons empiriquement de découvrir les impacts de l‟efficacité de l'action du pouvoir, comme un indice de qualité de gouvernance, sur la croissance économique via l‟investissement et le capital humain pour notre échantillon d‟étude. En dernier lieu, nous essayons de montrer les effets directs et indirects du contrôle de la corruption via l‟action du pouvoir public sur le développement économique à travers les secteurs de l‟éducation et de la santé. Ce travail cherche aussi à clarifier la manière d'amélioration des compétences et des niveaux de scolarisation du capital humain par l‟intermédiaire des allocations des dépenses publiques destinées aux secteurs de l‟éducation et de la santé. En outre et dans cette thèse, nous testons la complémentarité entre le rôle important de l'action du pouvoir public et le contrôle de la corruption qui représente un modèle d‟arbitrage dans une économie institutionnelle tout en utilisant un modèle à des équation simultanées durant la période (1984-2012) pour lesrégions d‟étude MENA-OCDE, MENA et OCDE. Au total, pour expliquer la relation entre le contrôle de la corruption et le développement économique via les secteurs sociaux de base, nous devons recourir à une synthèse économétrique forte pour montrer que la corruption a un effet social et elle a aussi des implications économiques et politiques sur notre échantillon d‟étude.

We address the issue of the dynamics of wealth accumulation and economic crisis triggered by extreme inequality, attempting to stick to most possibly intrinsic assumptions. Our general framework is that of pure or modified multiplicative processes, basically geometric Brownian motions. In contrast with the usual approach of injecting into such stochastic agent models either specific, idiosyncratic internal nonlinear interaction patterns, or macroscopic disruptive features, we propose a dynamic inequality model where the attainment of a sizable fraction of the total wealth by very few agents induces a crisis regime with strong intermittency, the explicit coupling between the richest and the rest being a mere normalization mechanism, hence with minimal extrinsic assumptions. The model thus harnesses the recognized lack of ergodicity of geometric Brownian motions. It also provides a statistical intuition to the consequences of Thomas Piketty's recent "$r>g$" (return rate $>$ growth rate) paradigmatic analysis of very-long-term wealth trends. We suggest that the "water-divide" of wealth flow may define effective classes, making an objective entry point to calibrate the model. Consistently, we check that a tax mechanism associated to a few percent relative bias on elementary daily transactions is able to slow or stop the build-up of large wealth. When extreme fluctuations are tamed down to a stationary regime with sizable but steadier inequalities, it should still offer opportunities to study the dynamics of crisis and the inner effective classes induced through external or internal factors., 15 pages, 11 figures. Work initiated from discussion on Aristotle's status revisited by Paul Jorion in the many cases where the law of supply and demand fails. Accepted for publication in Physical Review E on April 19, 2017

International audience This paper analyzes the socio-economic effects of energy sustainability challenges raised by oil depletion and climate change at the European and global level. We assess macroeconomic impacts at different time horizons over 2010-2100 and under different visions of the future of globalization . Fragmented capital markets affect the pace and direction of change and induce additional economic losses in the long term. Regionalized good markets have a positive effect in the long term since less intense international trade moderates the effects of fossil fuel constraints. A sustainable energy future will require implementing policies and measures that are able to (i) provide correct incentives for long-term investments by resorting to other signals than current market prices, (ii) incorporate sectoral measures that act complementarily to pricing schemes measures for sectors confronted with biased agents’ behaviors or strong inertias, (iii) foster globalization patterns that are consistent with energy sustainability objectives. The challenge consists in articulating the objectives and the instruments of these different policy and measures triggering the transition towards sustainable future.

A paraître dans Theory and Decision; International audience; For any TU game and any ranking of players, the set of all preimputations compat- ible with the ranking, equipped with the Lorenz order, is a bounded join semi-lattice. Furthermore the set admits as sublattice the S-Lorenz core intersected with the region compatible with the ranking. This result uncovers a new property about the structure of the S-Lorenz core. As immediate corollaries we obtain complementary results to the findings of Dutta and Ray, Games Econ. Behav., 3(4) p. 403-422 (1991), by showing that any S-constrained egalitarian allocation is the (unique) Lorenz greatest element of the S-Lorenz core on the rank-preserving region the allocation belongs to. Besides, our results suggest that the comparison between W- and S-constrained egalitarian allocations is more puzzling than what is usually admitted in the literature.

International audience; The El Khomri law (also called " Work law ") has triggered a lot of conflicting judgements among French economists. However no model has been used to evaluate its effects ex ante. We have developed over the past 10 years a model of the recent French labor market, in order to analyze in detail this market and do policy design and analysis. The model integrates the heterogeneity of agents, and their decisions (firms and workers) based on "search theory", which gives rational microe-conomic foundations to behavior, albeit with decision rules using bounded rationality rather than optimal rules which cannot be computed in the complex system that the modeled labor market constitutes. We introduce many institutions and specially the two main labor contracts, Open-Ended contracts and Fixed Term Contracts. The WorkSim model simulates the gross flows between inactivity, unemployment and these two types of employment, with a consistent accounting system. It is calibrated by a powerful algorithm to set 63 parameters to fit more than 64 aggregate real variables. We analyze only the facilitation of the economic dismissals allowed by the El Khomri law but it is the most essential element of the law for the labor market. We find that it has little effect on global unemployment but benefits the young who crowd out the seniors. This result is based on the substitution by the employers of more precarious Open Ended Contracts to Fixed Duration Contracts which become useless, and the fact that young workers are more often in Fixed Duration Contracts than the other age categories. The labor market is deeply transformed. When aggregate demand is exogenously changed, the experiment shows that the employment and the unemployment react faster than before the law.

International audience; Set functions are widely used in many domains of Operations Research (cooperative game theory, decision under risk and uncertainty, combinatorial optimization) under different names (TU-game, capacity, nonadditive measure, pseudo-Boolean function, etc.). Remarkable families of set functions form polyhedra, e.g., the polytope of capacities, the polytope of p-additive capacities, the cone of supermodular games, etc. Also, the core of a set function, defined as the set of additive set functions dominating that set function, is a polyhedron which is of fundamental importance in game theory, decicion making and com-binatorial optimization. This survey paper gives an overview of these notions and studies all these polyhedra.

We consider a financial model where the prices of risky assets are quoted by a representative market maker who takes into account an exogenous demand. We characterize these prices in terms of a system of BSDEs with quadratic growth. We show that this system admits a unique solution for every bounded demand if and only if the market maker's risk-aversion is sufficiently small. The uniqueness is established in the natural class of solutions, without any additional norm restrictions. To the best of our knowledge, this is the first study that proves such (global) uniqueness result for a system of fully coupled quadratic BSDEs., Comment: Published at http://dx.doi.org/10.1214/15-AAP1103 in the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)

The aim of this paper is to introduce a new formalism for the deterministic analysis associated with backward stochastic differential equations driven by general c{\`a}dl{\`a}g martingales. When the martingale is a standard Brownian motion, the natural deterministic analysis is provided by the solution of a semilinear PDE of parabolic type. A significant application concerns the hedging problem under basis risk of a contingent claim $g(X\_T,S\_T)$, where $S$ (resp. $X$) is an underlying price of a traded (resp. non-traded but observable) asset, via the celebrated F{\"o}llmer-Schweizer decomposition. We revisit the case when the couple of price processes $(X,S)$ is a diffusion and we provide explicit expressions when $(X,S)$ is an exponential of additive processes.

We study how the phenomenon of contagion can take place in the network of the world's stock exchanges due to the behavioral trait "blindeness to small changes". On large scale individual, the delay in the collective response may significantly change the dynamics of the overall system. We explicitely insert a term describing the behavioral phenomenon in a system of equations that describe the build and release of stress across the worldwide stock markets. In the mathematical formulation of the model, each stock exchange acts as an integrate-and-fire oscillator. Calibration on market data validate the model. One advantage of the integrate-and-fire dynamics is that it enables for a direct identification of cause and effect of price movements, without the need for statistical tests such as for example Granger causality tests often used in the identification of causes of contagion. Our methodology can thereby identify the most relevant nodes with respect to onset of contagion in the network of stock exchanges, as well as identify potential periods of high vulnerability of the network. The model is characterized by a separation of time scales created by a slow build up of stresses, for example due to (say monthly/yearly) macroeconomic factors, and then a fast (say hourly/daily) release of stresses through "price-quakes" of price movements across the worlds network of stock exchanges., 38 pages - jpg figures conveeted to pdf in this version

Despite the growing body of work devoted to the impacts of development and international trade flows on the environment, the current state of empirical research is still controversial. In this line of analysis, the empirical studies using panel data face two simultaneous challenges. One is associated with the potential presence of unobserved cross-country heterogeneity in the panel, and the other with the use of aggregate data on international trade. In this paper, we apply both the dynamic fixed effects and empirical iterative Bayes estimators to a global panel of annual data on 55 countries spanning the period 1970-2013, to show that when country heterogeneity is accurately accounted for in the estimation, it is possible to obtain significant impacts of trade variables on the environment, even with aggregate data. Based on the estimation results and further information on the stringency of environmental regulations in both developed and developing countries involved in the analysis, we identify different country groups having similar features with respect to the trade-environment relationship. Future multilateral actions and agreements on climate change should account for differences in countries' trade structures and development levels that determine their capabilities to mitigate and adapt to climate change.

We study linear properties of TU-games, revisiting well-known issues like interaction transforms, the inverse Shapley value problem and potentials. We embed TU-games into the model of cooperation systems and influence patterns, which allows us to introduce linear operators on games in a natural way. We focus on transforms, which are linear invertible maps, relate them to bases and investigate many examples (Mobius transform, interaction transform, Walsh transform and Fourier analysis etc.). In particular, we present a simple solution to the inverse problem in its general form: Given a linear value $${\Phi }$$ and a game v, find all games $$v'$$ such that $${\Phi (v)=\Phi (v')}$$ . Generalizing Hart and Mas-Colell’s concept of a potential, we introduce general potentials and show that every linear value is induced by an appropriate potential.

Wording has been widely shown to affect decision making. In this paper, we investigate experimentally whether and to what extent, cooperative behaviour in a Game of Chicken may be impated by a very basic change in the labelling of the strategies. Our within-subject experimental design involves two treatments. The only difference between them is that we introduce either a socially-oriented wording (‘I cooperate'/‘I do not cooperate') or colours (red/blue) to designate strategies. The level of cooperation appears to be higher in the socially-oriented context, but only when the uncertainty as regards the type of the partner is manipulated, and especially among females., On connaît l'importance des mots sur la perception des messages. L'impact de la terminologie employée sur la prise de décision a ainsi été largement docummenté. Dans cet article, nous tentons de répondre expérimentalement à la question suivante : dans quelle mesure le comportement de coopération dans un jeu de la poule mouillée est-il affecté par un changement mineur dans la dénomination des stratégies ? Notre protocole expérimental met en jeu deux traitements (soumis aux mêmes sujets). La seule différence entre ces traitements est que l'un utilise une terminologie qui met l'accent sur l'aspect relationnel des stratégies (‘je coopère'/‘je ne coopère pas'), tandis que l'autre opte pour une dénomination plus neutre de ce point de vue en recourant à des couleurs (rouge/bleu). Le principal résultat de l'étude est que les sujets tendent à coopérer davantage dans le contexte "relationnel", mais seulement lorsque l'incertitude concernant le type du partenaire dans le jeu varie, et les femmes plus que les hommes.

En dépit de son utilisation et de sa légitimité croissantes, l’expérimentation de laboratoire en économie fait parfois l’objet de critiques qui peuvent aller jusqu’à la remise en cause de la pertinence de l’outil. Sans prétendre à l’exhaustivité, nous revenons sur ceux de ces arguments qui revêtent selon nous un caractère discutable (parce qu’ils nous semblent selon les cas témoigner soit d’une tentation stratégique face à des résultats expérimentaux considérés comme gênants, soit d’une vision erronée des finalités et potentialités de la démarche, soit encore d’une lecture partielle de la réalité économique elle-même) afin de montrer que leur validité est au mieux locale et partielle. Nous en profitons pour rappeler les finalités de la méthode expérimentale, circonscrire son domaine d’application (c.-à-d. ses potentialités et limites) et indiquer quelques précautions d’utilisation., Despite its increasing use and legitimacy, experimental methodology in economics has been subject to some criticism, an extreme version of which concludes to its irrelevance to its object. With no claim to exhaustiveness, the paper presents and discusses some arguments that we consider to be questionable – because they are suspected to hide either a strategic temptation when facing unpleasant experimental results or a fallacious view of experimental goals and potentialities, or even an inadequate approach of economic reality itself – and shows that they are at best locally or partially valid. This allows us to remind the reader of the purposes of the experimental method, of its potentialities and limits as well as of some basic precautions to adopt.