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Generalized multi-view model: Adaptive density estimation under low-rank constraints
No full textWe study the problem of bivariate discrete or continuous probability density estimation under low-rank constraints. For discrete distributions, we assume that the two-dimensional array to estimate is a low-rank probability matrix. In the continuous case, we assume that the density with respect to the Lebesgue measure satisfies a generalized multi-view model, meaning that it is -Hölder and can be decomposed as a sum of components, each of which is a product of one-dimensional functions. In both settings, we propose estimators that achieve, up to logarithmic factors, the minimax optimal convergence rates under such low-rank constraints. In the discrete case, the proposed estimator is adaptive to the rank . In the continuous case, our estimator converges with the rate up to logarithmic factors, and it is adaptive to the unknown support as well as to the smoothness and to the unknown number of separable components . We present efficient algorithms for computing our estimators
Vehicle routing problems with multiple commodities: A survey
No full textInternational audienceIn this paper, we present a survey on vehicle routing problems with multiple commodities. In most routing problems, only one commodity is explicitly considered. This may be due to the fact that, indeed, a single commodity is involved, or multiple commodities are transported, but they are aggregated and modeled as a single commodity, as no specific requirement imposes their explicit consideration. However, there exist cases in which this aggregation is not possible due to the characteristics of the commodities or to the fact that it would lead to sub-optimal routing plans. This survey focuses on the analysis of the settings of the problems and the features of the commodities that require explicit consideration of disaggregated commodities in routing problems. We show that problem settings are inherently different with respect to the single commodity problems, and this has a consequence on both models and solution approaches, which cannot be straightforwardly adapted from the single commodity cases. We propose a classification of the routing problems with multiple commodities and discuss the motivations that force considering the presence of multiple commodities explicitly. Specifically, we focus on the modeling perspective by proposing a general formulation for routing problems with multiple commodities and showing how this formulation can be adapted to the different features that characterize the problem classes discussed in the survey. Also, 1 for each major class of problems, promising future research directions are discussed by analysing what has been studied in the current literature and focusing on challenging topics not covered yet
Nonstandard Errors
No full textInternational audienceIn statistics, samples are drawn from a population in a data‐generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence‐generating process (EGP). We claim that EGP variation across researchers adds uncertainty—nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer‐review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants
Etat des lieux des critères ESG dans la politique de rémunération des dirigeants mandataires sociaux
No full textThis study, conducted by the European Centre for Law and Economics (CEDE) at ESSEC, analyzes the integration of ESG (Environmental, Social, Governance) criteria into the remuneration policy of executive directors (DMS) of the CAC40, utilizing research carried out within the Women Board Ready ESSEC programme in 2023. In response to growing extra-financial challenges, the remuneration of DMS has evolved to include ESG objectives, aiming to encourage a serious consideration of these criteria in the strategies of major corporations, alongside the evolving legal framework. The inclusion of ESG criteria in remuneration packages is now a widespread practice among large European companies, though the weighting and nature of the criteria used vary significantly. Reports from the Responsible Investment Forum (FIR), based on annual questions during shareholder meetings of major corporations published between 2020 and 2024, show a growing trend in the integration of ESG criteria into the remuneration policies of CAC 40 companies. In 2023, 842 written questions were posed during general assemblies.Within the Women Board Ready ESSEC programme, participants of the 2023 cohort worked on addressing disparities in the application of ESG criteria. While 100% of CAC40 companies have included ESG criteria in short-term variable remuneration 3 since 2022, the ESG component in variable remuneration is 19.6% and 19.8% for the short and long terms, respectively. Only 23 CAC 40 groups provide a detailed breakdown of ESG criteria for the short term, and only 16 do so for the long term. This study also notes an imbalance in the types of ESG criteria considered, with a predominance of environmental criteria over social and governance criteria. Companies need to ensure that prioritized ESG indicators are clear, detailed, and aligned with meaningful performance objectives. The CSRD directive should serve as a tool for progress in this area, leading us to produce a second working paper on this topic and broader recommendations, to be published later.Cette étude, réalisée par le Centre Européen en Droit et Économie (CEDE) de l'ESSEC dans le cadre du programme Gouvernance responsable avec l’appui du CERESSEC, analyse l'intégration des critères ESG (Environnement, Social, Gouvernance) dans la politique de rémunération des dirigeants mandataires sociaux (DMS) du CAC40 en utilisant les travaux menés dans le cadre du Women Board Ready ESSEC en 2023.Face aux enjeux extra-financiers grandissants, les rémunérations des DMS ont en effet évolué pour inclure des objectifs ESG, visant à encourager une prise en compte sérieuse de ces critères dans la stratégie des grands groupes, tandis que le cadre légal évoluait en parallèle. L'inclusion de critères ESG dans les packages de rémunération est désormais une pratique répandue, parmi les grandes entreprises européennes, mais la pondération et la nature des critères utilisés varient considérablement. Les rapports du Forum pour l’Investissement Responsable (FIR)2 fondés notamment sur le réponses au questionnement annuel mené au cours des Assemblées générales des actionnaires, des grands groupes entre 2020 et 2024, montrent une tendance croissante à l'intégration des critères ESG dans les politiques de rémunération des entreprises du CAC 40, le tout dans un contexte d’interpellation de la dirigeance par les minoritaires: en 2023, 842 questions écrites ont ainsi été posées lors des assemblées générales.Dans le cadre du programme certifiant Women Board Ready ESSEC3, les participantes de la promotion 2023 nommées (note 1) ont travaillé sur ces questions des disparités dans l'application des critères ESG. Si 100% des entreprises du CAC40 intègrent des critères ESG dans la rémunération variable à court terme depuis 2022, la part ESG dans la rémunération variable est respectivement de 19,6% et 19,8% pour le court et le long termes et seuls 23 groupes du CAC 40 font preuve d’une décomposition fine des critères ESG pour le court terme, seulement 16 pour le long terme. L'étude réalisée que nous exposons ici note aussi une inégalité dans la prise en compte des types de critères ESG: prépondérance de critères environnementaux par rapport aux critères sociaux et de gouvernance. Les entreprises doivent avancer afin que veiller les indicateurs priorisés ESG soient clairs, détaillés et alignés sur des objectifs de performance significatifs et la directive CSRD devrait être à ce propos un outil de progression ce qui nous a conduit à produire un second WP que ce sujet et plus globalement les préconisations; qui sera publié ultérieurement
Logarithmic Smoothing for Pessimistic Off-Policy Evaluation, Selection and Learning
No full textThis work investigates the offline formulation of the contextual bandit problem, where the goal is to leverage past interactions collected under a behavior policy to evaluate, select, and learn new, potentially better-performing, policies. Motivated by critical applications, we move beyond point estimators. Instead, we adopt the principle of pessimism where we construct upper bounds that assess a policy's worst-case performance, enabling us to confidently select and learn improved policies. Precisely, we introduce novel, fully empirical concentration bounds for a broad class of importance weighting risk estimators. These bounds are general enough to cover most existing estimators and pave the way for the development of new ones. In particular, our pursuit of the tightest bound within this class motivates a novel estimator (LS), that logarithmically smooths large importance weights. The bound for LS is provably tighter than all its competitors, and naturally results in improved policy selection and learning strategies. Extensive policy evaluation, selection, and learning experiments highlight the versatility and favorable performance of LS
L’interaction public-privé dans le Grand Paris et le Grand Londres au prisme des écosystèmes de promotion économique
No full textInternational audienceUrban governance literature has yet to significantly contribute to explaining the divergent trajectories of cities. Focusing on the cases of Paris and London during the Third Industrial Revolution, this article highlights the existence of two highly unequal systems of public-private interrelations in these two cities—strong in London, weak in Paris—as well as an unequal medium-term capacity to produce coordinated strategic decisions at the metropolitan scale. It illustrates these two realities by comparing their economic promotion ecosystems, positing the hypothesis that urban economic governance, as a system of fluid and continuous interactions between economic actors and public authorities, plays a catalytic role in city dynamics through its function of reducing transaction costs.La littérature sur la gouvernance urbaine a encore peu contribué à expliquer en partie les trajectoires différenciées entre villes. Se focalisant sur le cas de Paris et de Londres durant la troisième révolution industrielle, cet article met en lumière l’existence pour ces deux villes de deux systèmes très inégaux d’interrelations public-privé – fortes à Londres, faibles à Paris – et d’une inégale capacité à moyen terme à produire des décisions stratégiques coordonnées à l’échelle métropolitaine. Il illustre ces deux réalités par la comparaison des écosystèmes de promotion économique, faisant l’hypothèse que la gouvernance économique des villes, en tant que système d’interactions fluides et permanentes entre acteurs économiques et puissance publique, joue un rôle catalyseur de la dynamique des villes, par sa fonction de diminution des coûts de transaction
Currency internationalization with Chinese characteristics: Is capital‐account convertibility required for the renminbi to acquire reserve‐currency status?
No full textInternational audienceIt is widely assumed that the renminbi (RMB) cannot acquire a meaningful place in central bank reserve portfolios without full liberalization of China's capital account. We argue that the RMB can in fact develop into an international reserve currency in the absence of capital‐account convertibility. Trade and investment links can drive use despite limited access to Chinese financial markets. But this route to currency internationalization requires policy support. China must provide access to RMB through loans and the People's Bank of China (PBoC) currency swaps. It must ensure the convertibility of RMB into US dollars in offshore markets. It must provide RMB services at a stable and predictable price. Currency internationalization without full capital‐account liberalization thus requires the RMB to be backed by dollar reserves, which the PBoC consequently will continue to hold and use. Hence, we do not foresee RMB internationalization as supplanting dollar dominance
Why Is Exclusivity in Broadcasting Rights Prevalent and Why Does Simple Regulation Fail?
No full textPay-TV firms compete both downstream to attract viewers and upstream to acquire broadcasting rights. Because profits inherited from downstream competition satisfy a convexity property, allocating rights to the dominant firm maximizes the industry profit. Such an exclusive allocation of rights emerges as a robust equilibrium outcome but may fail to maximize welfare. We analyze whether a ban on resale and a ban on package bidding may improve welfare. These corrective policies have no impact on the final allocation but lead to profit redistribution along the value chain
Real-world evaluation of mortality in patients with heart failure treated with Sacubitril-Valsartan in France
No full textInternational audienceIntroduction: Sacubitril-Valsartan was approved in Europe in 2015, for treatment of adults with symptomatic chronic heart fail ure (HF) with reduced left ventricular ejection fraction (HFrEF). In France, Sacubitril-Valsartan had firstly benefited from an early access program (2015–2018), and then became available in community pharmacy since October 2018.Objective: This study aims to describe characteristics of patients who received Sacubitril-Valsartan in France and to assess real-life all-cause mortality in this population.Method: This non-interventional retrospective study was based on existing claims data from the French National Healthcare Data System (SNDS) allowing long-term follow-up of patients who benefited from at least one reimbursement of Sacubitril-Valsartan. Data were collected between April 2012 to December 2020. Characteristics of patients were assessed at first reimbursement of Sacubitril-Valsartan and all-cause mortality was estimated using Kaplan-Meier method.Results:Between 2015 and 2020, 104,910 patients initiated Sacubitril-Valsartan treatment and were followed for an average of 20 months after initiation. Mean (SD) age of patients was 70.9 (12.9) years (with 42.6% 75 years), 72.1% were male, 31.9% had diabetes, ≥ and 93.4% had hypertension. 38.4% of patients were hospitalizedfor HF in the year prior to Sacubitril-Valsartan initiation, 20.5% did not receive angiotensin-converting–enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs) in the 6 months prior to Sacubitril-Valsartan initiation, 73.4% had beta-blockers, 38.3% had mineralocorticoid - receptor antagonists (MRAs), and 71.5% hadloop diuretics. In this study population, all-cause mortality was 6.0% [5.9–6.2%] at 6 months, 10.6% [10.4–10.8%] at 12 months, and 18.8% [18.5–19.1%] at 24 months.Conclusion: This study provides exhaustive nationwide data on Sacubitril-Valsartan real-world utilization and mortality in France over a 6-year period
Promotional Allowances: Loss Leading as an Incentive Device
No full textA retailer can boost demand for a manufacturer’s product through unobservable activities. Promotional allowances, which are retrospective rebates tied to the success of the retailer’s promotional efforts, can partially mitigate the resulting moral hazard problem. In equilibrium, the wholesale contract includes a retail price set below cost, complemented by a rebate for incremental units purchased when promotional efforts successfully increase sales. Loss leading thus emerges as an incentive mechanism, rather than a practice driven by anti-competitive or exploitative intent. A ban on below-cost pricing leads to higher retail prices and reduced promotional efforts