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Equality: What It Means and Why It Matters
No full textInternational audienceIn this compelling dialogue, two of the world’s most influential thinkers reflect on the value of equality and debate what citizens and governments should do to narrow the gaps that separate us. Ranging across economics, philosophy, history, and current affairs, Thomas Piketty and Michael Sandel consider how far we have come in achieving greater equality. At the same time, they confront head-on the extreme divides that remain in wealth, income, power, and status nationally and globally.What can be done at a time of deep political instability and environmental crisis? Piketty and Sandel agree on much: more inclusive investment in health and education, higher progressive taxation, curbing the political power of the rich and the overreach of markets. But how far and how fast can we push? Should we prioritize material or social change? What are the prospects for any change at all with nationalist forces resurgent? How should the left relate to values like patriotism and local solidarity where they collide with the challenges of mass migration and global climate change?To see Piketty and Sandel grapple with these and other problems is to glimpse new possibilities for change and justice but also the stubborn truth that progress towards greater equality never comes quickly or without deep social conflict and political struggle
Coupled THM simulation of high-frequency mechanical wave propagation and heat generation in the vicinity of a low permeable oil well
No full textInternational audienceCoupled THM simulation of high-frequency mechanical wave propagation and heat generation in the vicinity of a low permeable oil wel
Centrifuge study of a laterally loaded energy pile
No full textInternational audienceThis paper examines the displacements of energy piles laterally loaded in dry sand using the geotechnical centrifuge apparatus at Gustave Eiffel University. A 20D (D is the diameter of the pile) aluminium pile length is modelled (that is, 16 m length in the prototype) under the 26.7 g level in physical modelling. It is subjected to a horizontal load of 430 kN followed by 6 heating-cooling cycles. The accumulation of horizontal displacement is observed. The temperature of the thermal circuit inside the tubular pile and the pile’s surface is measured, and it is concluded that the pile’s deflection is primarily affected by the temperature on the it’s surface
Du crédit dispersé à la financiarisation
No full textInternational audienceThis chapter presents the transformations of French financial organizations and institutions since the early XIXth century. It aims at synthetizing the existing litterature and providing a broad interpretation fo the transformations observed, building on research in economics, history and sociology
Playing with Kruskal: algorithms for flat and hierarchical watershed cuts
No full textIn the framework of edge-weighted graphs, watersheds have proven to be linked to well-know optimization problems, as Minimum Spanning Tree, which allowed the design of efficient algorithms for computing (hierarchical) watershed segmentations. In the literature, such algorithms have been partially described and analyzed across several works, but a detailed description of the complete pipeline is still lacking. In the present paper, we rely on those previous works to present a detailed end-to-end pipeline of algorithms to compute (hierarchical) watershed segmentations, starting from the computation of graph-based image representations, up to the computation of connected components of the final (hierarchical) segmentation. We consider the several variations of watersheds, including their supervised and unsupervised versions, and the various ways of computing seeds, to name a few. For the first time, we bring together all these watershed notions and algorithms in a compact and understandable way. We aim at providing a reference for those interested in employing and reimplementing the watershed segmentation framework for their task at hand
Analyse événementielle
No full textL’analyse événementielle permet de mesurer l’impact d’un événement donné (typiquement, une intervention) sur une ou plusieurs variables d’intérêt, en comparant à un moment donné des individus qui ont déjà bénéficié de l’intervention à d’autres pour qui ce n’est pas encore le cas. Cette méthode d’analyse contrefactuelle se rapproche de celle des doubles différences
Formation of international environmental agreements and payoff allocation
No full textDocuments de travail du Centre d'Economie de la Sorbonne 2025.20 - ISSN : 1955-611X - eISSN : 2968-6687Dealing with climate change requires that all countries engage in costly efforts to reduce their emissions. Reaching this objective has so far been elusive because it is in the best interest of each country to let the others do the effort and benefit itself from a better environment. The presence of negative externalities and strategic behavior have made game theory a natural paradigm to design an international environmental agreement (IEA) that codifies what countries should do. Considering that countries are sovereign and no supranational entity can impose an agreement, a stream of literature adopted a noncooperative mode of play to the formation of an environmental coalition. On the other hand, as joint optimization of all countries' payoff leads to the best outcome, cooperative games approach has also been proposed to share the cost of climate change. Both approaches have their pros and cons.In this paper, we propose a model of coalition formation that combines both cooperative and noncooperative modes of play. Starting from any given coalition, we implement a Markov process that shows sequentially which countries join or leave the coalition until reaching an absorbing state. All possible sequential scenarios are considered and an allocation to the player is made taking into account individual rationality. An illustration with vulnerable and invulnerable countries to pollution is given.</p
Effective Asymptotics of Combinatorial Systems
No full textAnalytic combinatorics studies asymptotic properties of families of combinatorial objects using complex analysis on their generating functions. In their reference book on the subject, Flajolet and Sedgewick describe a general approach that allows one to derive precise asymptotic expansions starting from systems of combinatorial equations. In the situation where the combinatorial system involves only cartesian products and disjoint unions, the generating functions satisfy polynomial systems with positivity constraints for which many results and algorithms are known. We extend these results to the general situation. This produces an almost complete algorithmic chain going from combinatorial systems to asymptotic expansions. Thus, it is possible to compute asymptotic expansions of all generating functions produced by the symbolic method of Flajolet and Sedgewick when they have algebraic-logarithmic singularities (which can be decided), under the assumption that Schanuel's conjecture from number theory holds. That conjecture is not needed for systems that do not involve the constructions of sets and cycles
Endogenous Clustering and Analogy-Based Expectation Equilibrium
No full textInternational audienceNormal-form two-player games are categorized by players into K analogy classes so as to minimize the prediction error about the behavior of the opponent. This results in Clustered Analogy-Based Expectation Equilibria in which strategies are analogy-based expectation equilibria given the analogy partitions and analogy partitions minimize the prediction errors given the strategies. We distinguish between environments with self-repelling analogy partitions in which some mixing over partitions is required and environments with self-attractive partitions in which several analogy partitions can arise, thereby suggesting new channels of belief heterogeneity and equilibrium multiplicity. Various economic applications are discussed
Đổi mới sáng tạo để thoát bẫy nghèo khó, bẫy thu nhập trung bình và bẫy tăng trưởng trung bình?
No full textIn the context of globalization and intensifying economic competition, Vietnam has achieved remarkable progress in economic growth and improving living standards over the past few decades. However, significant challenges persist, particularly the risk of falling into development traps such as the poverty trap, the middle-income trap, and the average growth rate trap.Vietnam is currently classified as a lower-middle-income country, with a GDP per capita of approximately USD 4,700 in 2024. According to a World Bank report (Coppola et al., 2024), achieving the goal of becoming a high-income country by 2045 requires Vietnam to sustain a high and consistent economic growth rate. This article analyzes the core factors driving economic growth, defines the types of development traps, and proposes innovation- and technology-based (I&T) solutions to help Vietnam overcome these challenges. The analysis draws on data and insights from official sources, such as the General Statistics Office of Vietnam (GSO) and international organizations, to substantiate the arguments. This article does not address the risks posed by U.S. tariff policies, which significantly impact Vietnam—one of the economies heavily reliant on foreign markets—and contribute to the reconfiguration of the global trade order.Trong bối cảnh toàn cầu hóa và cạnh tranh kinh tế ngày càng gay gắt, Việt Nam đã đạt được những thành tựu đáng kể trong việc tăng trưởng kinh tế và cải thiện đời sống người dân trong vài thập kỷ qua. Tuy nhiên, những thách thức lớn vẫn còn tồn tại, đặc biệt là nguy cơ rơi vào các bẫy phát triển như bẫy nghèo khó, bẫy thu nhập trung bình và bẫy tốc độ tăng trưởng trung bình.Việt Nam hiện đang ở nhóm các nước có thu nhập trung bình thấp với GDP bình quân đầu người đạt khoảng 4.700 USD vào năm 2024. Theo báo cáo của Ngân hàng Thế giới - World Bank (Coppola và cộng sự, 2024) để đạt được mục tiêu trở thành quốc gia có thu nhập cao vào năm 2045, Việt Nam cần duy trì tốc độ tăng trưởng kinh tế cao và bền vững. Bài viết này sẽ phân tích các yếu tố cốt lõi thúc đẩy tăng trưởng kinh tế, định nghĩa các loại bẫy phát triển, đồng thời đề xuất các giải pháp dựa trên đổi mới sáng tạo (ĐMST) để Việt Nam vượt qua những thách thức này. Chúng tôi cũng sẽ kết hợp các dữ liệu và phân tích từ các nguồn chính thức như Tổng cục Thống kê Việt Nam (GSO) và các tổ chức quốc tế để làm rõ các luận điểm. Bài viết này không nói đến các nguy cơ đến từ chính sách thuế quan của Mỹ, đang có tác động mạnh mẽ đến Việt Nam, là một trong những nền kinh tế rất phụ thuộc vào thị trường nước ngoài, và gây sắp xếp lại trật tự thương mại toàn cầu