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Ecosystem recovery from anthropogenic disturbances, either without human intervention or assisted by ecological restoration, is increasingly occurring worldwide. As ecosystems progress through recovery, it is important to estimate any resulting deficit in biodiversity and functions. Here we use data from 3,035 sampling plots worldwide, to quantify the interim reduction of biodiversity and functions occurring during the recovery process (that is, the 'recovery debt'). Compared with reference levels, recovering ecosystems run annual deficits of 46&-51% for organism abundance, 27&-33% for species diversity, 32&-42% for carbon cycling and 31&-41% for nitrogen cycling. Our results are consistent across biomes but not across degrading factors. Our results suggest that recovering and restored ecosystems have less abundance, diversity and cycling of carbon and nitrogen than 'undisturbed' ecosystems, and that even if complete recovery is reached, an interim recovery debt will accumulate. Under such circumstances, increasing the quantity of less-functional ecosystems through ecological restoration and offsetting are inadequate alternatives to ecosystem protection., The National Socio-Environmental Synthesis Center, German Helmholtz Centre for Environmental Research, Synthesis Centre for Biodiversity Sciences

International audience; This paper considers the case of two competing, nested, probability predicting models. The nested model contains traditional factors, and thelarger model contains some expensive, or generally hard to obtain, often genetic, relevant markers. The indices used to compare the respectivepredictive ability of the two models are the integrated discrimination improvement (IDI) and the Brier's score improvement (BRI). Estimation of themodels and their relative IDI and BRI are conducted on the same sample, and their respective asymptotic properties are proved. The results areapplied to Alzheimer's disease. The authors conduct two different simulations: one to check the behavior of the estimates of IDI and BRI, and theother parallel to Gu and Pepe's examples. The three city (3C) study is a cohort study conducted in three cities in France (Bordeaux, Dijon andMontpellier), aiming to estimate the risk of dementia and cognitive impairment attributable to vascular factors.

International audience; Both regulatory agencies and nonprofit organizations seek to understand how different tactics and appeals contained in food and public health advertisements might influence the food intake of an increasingly dieting-concerned population. This article addresses this important issue by examining how consumers who are concerned with their diets react to rich images of unhealthy food consumption. Results of two experiments show that exposure to food advertisements containing unhealthy food consumption imagery reduces food intake among consumers chronically concerned with dieting, whereas a third experiment shows a similar decrease in intended consumption when a public health advertisement portrays the consumption of unhealthy food. These findings in turn offer guidelines for maximizing the effectiveness of messages that attempt to promote healthy eating habits. Additionally, this research provides theoretical contributions to the self-control and mental imagery research domains which have public policy implications for regulatory agencies and nonprofit organizations.

In every liter of seawater there are between 10 and 100 billion life forms, mostly invisible, called marine plankton or marine microbiome, which form the largest and most dynamic ecosystem on our planet, at the heart of global ecological and economic processes. While physical and chemical parameters of planktonic ecosystems are fairly well measured and modeled at the planetary scale, biological data are still scarce due to the extreme cost and relative inflexibility of the classical vessels and instruments used to explore marine biodiversity. Here we introduce ‘Plankton Planet’, an initiative whose goal is to engage the curiosity and creativity of researchers, makers, and mariners to (i) co-develop a new generation of cost-effective (frugal) universal scientific instrumentation to measure the genetic and morphological diversity of marine microbiomes in context, (ii) organize their systematic deployment through coastal or open ocean communities of sea-users/farers, to generate uniform plankton data across global and long-term spatio-temporal scales, and (iii) setup tools to flow the data without embargo into public and explorable databases. As proof-of-concept, we show how 20 crews of sailors were able to sample plankton biomass from the world surface ocean in a single year, generating the first seatizen-based, planetary dataset of marine plankton biodiversity based on DNA barcodes. The quality of this dataset is comparable to that generated by Tara Oceans and is not biased by the multiplication of samplers. The data unveil significant genetic novelty and can be used to explore the taxonomic and ecological diversity of plankton at both regional and global scales. This pilot project paves the way for construction of a miniaturized, modular, evolvable, affordable and open-source citizen field-platform that will allow systematic assessment of the eco/morpho/genetic variation of aquatic ecosystems and microbiomes across the dimensions of the Earth system.

International audience; We study multi-period college admission problems where, at each period, a matching is computed and students have the option to either finalize their matches or participate to the next period. Students participating to an additional run of the matching mechanism can submit a new rank order list to the matching clearinghouse. Such gradual matching systems can adequately account for an additional source of heterogeneity among participants, like withdrawals. We identify the conditions under which such systems first ensure that participating to additional runs of the matching mechanism is safe for participants (in the sense that they can secure the spot they obtained at the previous round) and second yield to stable matchings (with a stability concept adapted to this environment). We use our results to evaluate the former French college admission system, where students could finalize their matches at different dates up to two months ahead the end of the admission campaign.

We present here the statistical models that are most in use in survival data analysis. The parametric ones are based on explicit distributions, depending only on real unknown parameters, while the preferred models are semi-parametric, like Cox model, which imply unknown functions to be estimated. Now, as big data sets are available, two types of methods are needed to deal with the resulting curse of dimensionality including non informative factors which spoil the informative part relative to the target: on one hand, methods that reduce the dimension while maximizing the information left in the reduced data, and then applying classical stochastic models; on the other hand algorithms that apply directly to big data, i.e. artificial intelligence (AI or machine learning). Actually, those algorithms have a probabilistic interpretation. We present here several of the former methods. As for the latter methods, which comprise neural networks, support vector machines, random forests and more (see second edition, January 2017 of Hastie, Tibshirani et al. (2005) [1] ), we present the neural networks approach. Neural networks are known to be efficient for prediction on big data. As we analyzed, using a classical stochastic model, risk factors for Alzheimer on a data set of around 5000 patients and p = 17 factors, we were interested in comparing its prediction performance with the one of a neural network on this relatively small sample size data.

In a two-sided matching context we show how we can predict stable matchings by considering only one side’s preferences and the mutually acceptable pairs of agents. Our methodology consists of identifying impossible matches, i.e., pairs of agents that can never be matched together in a stable matching of any problem consistent with the partial data. We analyze data from the French academic job market for mathematicians and show that the match of about 45 percent of positions (and about 60 percent of candidates) does not depend on the preferences of the hired candidates, unobserved and submitted at the final stage of the market. (JEL C78, I23, J41, J44)

The “Vida de Anacreonte”, one of the several paratexts from Francisco de Quevedo’s Anacreón castellano, is a translation and adaptation of the Vita Anacreontis writtenin Latinby the 16th-century humanist Lilio Gregorio Giraldi.This article analyzes Quevedo’s Spanish rewriting of Giraldi’s biography, its significance within the profuse paratextual apparatus of the Anacreón castellano, as well as the most significant rhetorical and dialectic strategies exploited by Quevedo to defend the Greek poet and justify his paraphrastic version of the odes., La “Vida de Anacreonte”, uno de los paratextos del Anacreón castellano de Quevedo, es una traducción y reescritura de la Vita Anacreontis del humanista Lilio Gregorio Giraldi. Este artículo analiza los cambios introducidos por Quevedo a partir del texto latino, su significación dentro del conjunto paratextual, así como los recursos retóricos y dialécticos más sobresalientes del discurso judicial empleados por Quevedo para defender al poeta griego y justificar la paráfrasis de las odas al español.

Lecture Notes in Computer Science book series (LNCS, volume 11890); International audience; The order of criticality of a player in a simple game and two indices inspired by the reasoning à la Shapley and à la Banzhaf were introduced in two previous papers [3] and [4], respectively, mainly having in mind voting situations. Here, we devote our attention to graph connection games, and to the computation of the order of criticality of a player. The indices introduced in [4] may be used as centrality measures of the edges in preserving the connection of a graph.

International audience; In the current context of digital transformation of the way organizations operate and are designed, the purpose of this paper is to rethink the concept of rationality in order to provide new insights on how the choices made individually by social actors could help to shape sociotechnical change at the organizational and societal levels. We propose a theoretical synthesis of the principal conceptions of rationality in the social sciences: that is, the dominant theory of rational choice and other critical approaches developed, among others, by Foucault, Habermas, Boudon, and Archer. The paper revisits and reconciles the views developed by the latter two authors in particular. Boudon favors an enlarged conception of rationality (called ordinary rationality), as developed by Weber (1922), which includes the instrumentalist, normative, and representational dimensions. We propose to associate this model with the reflexivity model developed by Archer (2003) in order to define a new approach: reflexive ordinary rationality, which is based upon three underlying ideas: (1) The unit of analysis of social action is the individual; (2) Social structures affect and are affected by individual actions; (3) Behind each individual action there is a system of reasons related to certain modes of reflexivity that we can define. Hence, this paper proposes a new analytical framework for studying current and future sociotechnical changes related to the interactions between individuals and digital technologies.; Dans le contexte actuel de transformation digitale des modes de fonctionnement des organisations et de leur design, cet article propose un recadrage conceptuel de la notion de rationalité des acteurs organisationnels afin de comprendre comment les choix que ces derniers effectuent tout au long de leurs interactions avec les technologies et systèmes d’information contribuent au modelage de changements sociotechniques sur le plan organisationnel et sociétal. Nous proposons une synthèse théorique sur les principales conceptions de la rationalité en sciences sociales. À savoir, l’approche dominante de la théorie du choix rationnel et les approches critiques développées notamment par Foucault, Habermas, Archer et Boudon. Plus particulièrement, l’article revisite et réconcilie les visions de ces deux derniers auteurs. Boudon préconise en effet une conception élargie (dite ordinaire) de la rationalité des acteurs telle que définie par Weber (1922), qui implique à la fois les dimensions utilitariste, normative et représentationnelle. Nous proposons d’associer à ce modèle les modes de réflexivité développés par Archer (2003) pour définir une nouvelle approche : la rationalité ordinaire réflexive. Trois idées clés fondent notre réflexion : (1) l’unité d’analyse de l’action sociale est l’individu ; (2) les structures sociales affectent et sont affectées par les actions individuelles ; (3) derrière chaque action individuelle, il y a un système de raisons associées à certains modes réflexifs que l’on peut définir. À ce titre, cet article propose un nouveau cadre analytique des changements sociotechniques actuels et à venir issus des interactions entre individus et technologies digitales.

International audience; This research investigates the interplay between leadership styles and institutional corporate social responsibility (CSR) practices. A large-scale field survey of managers reveals that firms with greater transformational leadership are more likely to engage in institutional CSR practices, whereas transactional leadership is not associated with such practices. Furthermore, stakeholder-oriented marketing reinforces the positive link between transformational leadership and institutional CSR practices. Finally, transactional leadership enhances, whereas transformational leadership diminishes, the positive relationship between institutional CSR practices and organizational outcomes. This research highlights the differential roles that transformational and transactional leadership styles play for a firm’s institutional CSR practices and has significant implications for theory and practice.

International audience; While companies contribute in different ways to the corporate social responsibility (CSR) issues they support, little is known about the effects of varying CSR contribution types on consumers’ evaluations of the contributing company. This paper examines consumer reactions to two basic contribution types – money versus in-kind – in the CSR domain of disaster relief to demonstrate, through five studies, that while consumers evaluate a company more favorably when it makes in-kind rather than monetary contributions of equivalent value to CSR issues that are perceived to be less controllable, the pattern reverses when the company’s contributions are made to CSR issues that are perceived to be more controllable. This interaction between contribution type and perceived issue controllability is more likely to manifest when controllability is accessible in the minds of consumers. The underlying process is driven by the extent to which the disparate emotionality of each contribution type matches the intensity of felt emotion evoked by CSR issues of varying perceived controllability, producing processing fluency.

International audience; Power indices in simple games measure the relevance of a player through her ability in being critical, i.e. essential for a coalition to win. We introduce new indices that measure the power of a player in being decisive through the collaboration of other players. We study the behavior of these criticality indices to compare the power of different players within a single voting situation, and that of the same player with varying weight across different voting situations. In both cases we establish monotonicity results in line with those of Turnovec [1998]. Finally, we examine which properties characterizing the indices of Shapley–Shubik and Banzhaf are shared by these new indices.

International audience; The authors focus on the problem of investigating the blackmail power of players in simple games, which is the possibility of players of threatening coalitions to cause them loss using arguments that are (apparently) unjustified. To this purpose, the classical notion of the criticality of players has been extended, in order to characterize situations where players may gain more power over the members of a coalition thanks to collusion with other players.

In a school choice context we show that considering only schools' priorities and the set of acceptable schools for each student - but not how these schools are ranked in their preferences - we can restrict the set of possible stable matchings that can arise for any preference profile of the students that leaves the set of acceptable schools unchanged. We characterize impossible matches, i.e., of pairs student school that cannot be matched at any stable matching, for any preference profile. Our approach consists of linking Hall's marriage condition to stable matchings. Our results offer a new methodology to assess to what extent the preferences on one side of a matching market can preset the stable matchings that can emerge. First, we use this technique to discuss the impact of priority zoning in school choice problems. Second, a new mechanism for school choice problems is proposed. It is shown that it (weakly) Pareto dominates the Student Optimal Stable Mechanism and retain some of its incentives.

Histone modifications are critical for the regulation of gene expression, cell type specification, and differentiation. However, evolutionary patterns of key modifications that regulate gene expression in differentiating organisms have not been examined. Here we mapped the genomic locations of the repressive mark histone 3 lysine 27 trimethylation (H3K27me3) in four species of Drosophila, and compared these patterns to those in C. elegans. We found that patterns of H3K27me3 are highly conserved across species, but conservation is substantially weaker among duplicated genes. We further discovered that retropositions are associated with greater evolutionary changes in H3K27me3 and gene expression than tandem duplications, indicating that local chromatin constraints influence duplicated gene evolution. These changes are also associated with concomitant evolution of gene expression. Our findings reveal the strong conservation of genomic architecture governed by an epigenetic mark across distantly related species and the importance of gene duplication in generating novel H3K27me3 profiles.

This paper is composed of a series of reflections on some aspects of the relation between politics and opera. It focuses on Verdi and Wagner. This year marks the bicentenary of both composers and Mitchell Cohen, a professor of political science at the City University of New York compares the political ideas in operas (and in other writings) by both composers. Both men are identified with nationalism, but their nationalisms were radically different., Cet article est composé d'une série de réflexions concernant quelques aspects de la relation entre la politique et l'opéra. Il se focalise sur les compositeurs Verdi et Wagner dont on fête le bicentenaire cette année. Mitchell Cohen en tant que professeur de science politique à la CUNY, compare les idées politiques des opéras et d'autres écrits de deux compositeurs. Malgré le fait que les deux s'identifient au nationalisme, leur pensée représente des formes de nationalisme radicalement différentes.

Alvin Roth and Lloyd Shapley have received in 2012 the Sveriges Riksbank prize in economic sciences in memory of Alfred Nobel, for their work on the centralized organization of some economic markets, which rely on the matching of agents of two different types (students and schools, for instance). Shapley is the co-author, with David Gale, of the seminal paper of the area, which proposes an algorithm to reach a stable matching. Roth directed the reform of the entry level labor market for American physicians (the National Resident Matching Program) and the design of a market for kidney transplants. After having surveyed these contributions, we also give an account of Shapley's leading role in game theory., Alvin Roth et Lloyd Shapley ont reçu en 2012 le prix de sciences économiques de la Banque Royale de Suède à la mémoire d'Alfred Nobel, pour leurs travaux sur l'organisation centralisée de certains marchés économiques, qui dépendent de l'appariement d'agents de deux types distincts (des élèves et des écoles, par exemple). Shapley est le co-auteur, avec David Gale, de l'article fondateur du domaine, qui propose un algorithme pour atteindre un appariement stable. Roth a dirigé la restructuration de la procédure d'affectation des internes dans les hôpitaux aux Etats Unis et la conception d'un marché lié à la transplantation de reins. Après avoir rendu compte de ces contributions, nous évoquons aussi le rôle déterminant de Shapley en théorie des jeux.

http://faculty.chicagobooth.edu/ioanid.rosu/research/mergers.pdf; Working Paper, University of Chicago, Booth School of Business; When a cash merger is announced but not completed, there are two main sources of uncertainty related to the target company: the probability of success and the price conditional on the deal failing. We propose an arbitrage-free option pricing formula that focuses on these sources of uncertainty. We test our formula in a study of all cash mergers between 1996 and 2008 which have sufficiently liquid options traded on the target company. The estimated success probability is a good predictor of the deal outcome. Our option formula for cash mergers does significantly better than the Black– Scholes formula and produces a volatility smile close to the one observed in practice. In particular, we provide an explanation for the kink in the volatility smile and show that the kink increases with the probability of deal success.

International audience

Cahier de Recherche du Groupe HEC Paris, n° 877; Three experiments investigate the role of expertise as a moderator of the relationship between implicit and explicit measures of attitudes. Prior research seems to suggest that greater expertise with an attitude object should lead to stronger implicit-explicit correlations. However, a cognitive view of expertise can also predict a weaker implicit-explicit relation. We lay out a framework that helps predict the directionality of the effect of expertise on the implicit-explicit relation and resolve that seeming contradiction. Our framework is based on the availability and accessibility of either detailed attribute information versus global attitudes in explicit attitude measures. We show that object-related and contextual factors differentially affect the availability and accessibility of these two different types of information for novices versus experts, thus determining how expertise moderates the implicit-explicit relation across different evaluation contexts.

International audience; Cet article compare le degré de pertinence de l’âge subjectif pour segmenter le marché de la mode vestimentaire dans quatre pays : la Chine, la Corée du Sud, la France et les États-Unis. Après avoir validé une nouvelle échelle de mesure invariante entre les différentes cultures, les effets de l’âge subjectif sont mis en évidence sur l’innovativité et la fréquentation des médias. Les résultats obtenus permettent d’envisager la mise en œuvre d’une stratégie de standardisation relative fondée sur l’âge subjectif dans le secteur de l’habillement.

Cahier de Recherche du Groupe HEC Paris, n° 720; We consider a model of endogenous occupational choice in economies with a continuum of individuals who differ in their wealth endowments. Individuals have a choice of remaining self-employed or engaging in productive matches with other individuals, i.e., forming "firms''. Such matches are subject to a hidden-action moral hazard problem with a limited liability constraint. This leads to wealth effects and the payoff-relvance of wealth differences across individuals. We suppose that the division of the gains from such matches is endogenous and determined by competitive market forces but that contracts are chosen optimally within matches subject to the market determined division of the gains from matching. We show, in contrast to previous results in the literature, that even when financial markets are perfect, the equilibrium distributions of occupations, utilities and surplus depend on the distribution of wealth in the economy. When financial markets are imperfect however, the equilibrium might involve the economy "segregating'' into a high-surplus rich sector and a low-surplus poor sector, independent of the distribution of wealth in the economy. We also characterize the nature of the equilibrium as a function of financial market imperfections and also as a function of the nature (symmetry) of the underlying agency problem within a firm.

Cahier de Recherche du Groupe HEC Paris, n° 683; We study competitive equilibria with moral hazard in economies with aggregate risk and where trading occurs with an incomplete set of financial assets. The main conclusion of the paper is that, contrary to the individual risk economies, moral hazard is compatible with trading in competitive linear financial contracts, and gives rise to no manipulation problem. We establish existence of nonmanipulable equilibria provided that there are no relative price effects (e.g. a one-commodity economy), and that ...nancial markets display nonlinearly homogeneous payoffs (e.g., nominal), and are sufficiently incomplete. Finally, we justify the linear contract as the optimal pricing schedule in a specific trading game with an auctioneer.

International audience; While Industry 4.0 has been trending in practice and research, operations management studies in this area remain nascent. Our intent is to understand the current state of research in Industry 4.0 in different disciplines and deduce insights and opportunities for future research in operations management. In this paper, we provide a focused analysis to examine the state-of-the-art research in Industry 4.0. To learn about researchers' perspectives about Industry 4.0, we conducted a large-scale, cross-disciplinary and global survey on Industry 4.0 topics among researchers in industrial engineering, operations management, operations research, control and data science at the 9 th IFAC MIM 2019 Conference in Berlin in August 2019. By using our survey findings and literature analysis, we build structural and conceptual frameworks to understand the current state of knowledge and to propose future research opportunities for operations management scholars.