Patricia Crifo develops the question of air conditioners in China for Polytechnique Insights.
17/09/2025
A New Academic Year, New Faces at CREST
Every year, CREST welcomes a new cohort of researchers who bring fresh perspectives, curiosity, and energy to our community. This fall, we are pleased to host new researchers, postdoctoral fellow, PhD students, and visiting researchers from around the world.
Their arrival marks an important moment in the life of our lab: the opportunity to grow, to renew dialogues across disciplines, and to continue building a vibrant and diverse research environment. Whether they join us for a few months or several years, these newcomers contribute to the intellectual richness and collaborative spirit that define CREST.
We are pleased to introduce the researchers who are joining CREST this year, each bringing their unique background and expertise to our four research areas: economics, sociology, statistics, and finance-insurance.
Researchers
This year, several new researchers are joining CREST, strengthening our core faculty and bringing new perspectives across ou disciplines.
Philippe Coulangeon is a CNRS Research Director, affiliated with the Centre for Research on Social Inequalities (CRIS) at SciencesPo Paris.
His work is set at the intersection of cultural sociology and social inequalities. He explores the stratification of cultural practices and tastes, the dynamics of mass versus elite culture, artistic professions, and the democratization of culture. More recently, he has integrated environmental concerns into his analysis.
Fanny Landaud is a CNRS researcher from CY Cergy Paris University and she is an IZA Research Fellow since 2019.
Her research covers applied microeconomics – particularly labor, education, family, and health economics – with a focus on the determinants and consequences of socioeconomic and gender inequalities in education and the labor market.
Antonio Ocello was a Postdoctoral Researcher in Statistics and Machine Learning at École polytechnique (CMAP) since 2023.
His research focuses on mean-field games and mean-field control problems, branching diffusion processes, and stochastic optimal control, combining advanced probabilistic methods with applications in machine learning. He has contributed to work on convergence bounds for trust-region policy optimization in mean-field games and is developing stochastic target frameworks for branching processes.
Enrico Ruolino was a Senior Researcher at the University of Lausanne.
His work focuses on public and labor economics, with a particular emphasis on behavioral responses to tax policy, gender inequality, intergenerational mobility, and educational outcomes.
Clémentine Van Effenterre was previously an Assistant Professor of Economics at the University of Toronto.
Her research lies at the intersection of labor economics, applied microeconomics, and political economy. Notably, she investigates how norms, institutions, and policies shape labor market outcomes – examining issues like maternal labor supply, gender gaps in science and tech, and how having daughters influences political attitudes. She also hosts the “InequaliTalks” podcast on economics and inequality.
Postdoctoral Fellows
Our new postdoctoral researchers are contributing to ongoing projects and launching their own work in close collaboration with CREST teams.
Stéphane Lhaut, in the Finance-Insurance team, with Caroline Hillairet and Olivier Lopez.
Angelica Martinez-Leyva, in the Economics cluster at CREST-ENSAI, with Marion Goussé
Andrea Pandolfi, in Statistics, with Nicolas Chopin
Arthur Stephanovitch, in Statistics, with Austin Stromme
Lishu Zhang, in the Finance-Insurance team, with Olivier-David Zerbib
PhD Students
This year, we welcome a new cohort of PhD students who are beginning their research journeys within our vibrant academic community.
30 new PhD students are joining our laboratory in our different research clusters.
9 PhD students will join our Economic team, 7 in the Finance-Insurance cluster, 12 new PhD students in Statistics, and 2 in our Sociology team.
4 of them will join our lab on the CREST-ENSAI campus in Bruz while the remaining PhD students will join our CREST-ENSAE Paris campus in Palaiseau.
This new team will also be joined by 3 PhD students in ATER contracts in the CREST-ENSAI campus.
Visiting Researchers
CREST is also hosting several visiting researchers this year, joining us for research stays that foster international collaboration.
Yang Chen (Lausanne University, Switzerland) is joining our Economic team to work with Julien Combe on Microeconomic theory and matching theory.
Matias Ortiz (Universidad de Chile, Chile) will work with Vianney Perchet on Learning-Augmented Online Algorithms for Matroid-Constrained problems under Partial in our Statistical team.
Simon Luck (Universita di Bologna, Italy) is joining Etienne Ollion’s team in Sociology to work on using natural language processing to study the relevance of the news media for political representation and decision-making processes.
Jules Verin (ENS Lyon, France) will work with Bertrand Garbinti in Economics on Wealth Accumulation, Life Cycle, and Taxation.
Väinö Yrjänäinen (Uppsala University, Sweden) is joining the Sociology team with Etienne Ollion to work on using work embeddings and transformer models in computational social sciences.
L’IA générative est-elle un gain pour la recherche ?
Bayesian Bi-level Sparse Group Regressions for Macroeconomic Density Forecasting
CREST Working Papers Series No. 2025-12
by Matteo Mogliani and Anna Simoni
Do Billionaires Pay Taxes?
CREST Working Papers Series No. 2025-11
by Laurent Bach, Antoine Bozio, Arthur Guillouzouic and Clément Malgouyres
Summer School on Environmental Data Collection and Analysis for the Social Sciences
From June 2 to 6, 2025, the Energy4Climate (E4C) Interdisciplinary Center and CREST brought together 20 participants for a Summer School on Environmental Data Collection and Analysis for the Social Sciences.
Over the course of one week, participants took part in lectures, workshops, and group activities designed to strengthen their skills and foster collaboration. A special highlight of this edition was the opportunity to join shared sessions with Columbia University, made possible through the Alliance partnership. These exchanges created a unique space for dialogue between institutions and disciplines, all centered on the challenges of climate and energy transitions.
This Summer School was made possible thanks to the generous support of the Fondation de l’École polytechnique and the Fonds Ifker pour le Climat. Their commitment played a key role in making the program accessible and impactful for the next generation of researchers.
We extend our warm thanks to all speakers and participants who contributed to the success of this edition.
Relive the Summer School experience and hear directly from participants in the video below
Quand l’histoire économique éclaire les accord commerciaux
Le 25 août 2024, Béatrice Cherrier, historienne de l’économie, chargée de recherche au CNRS, chercheuse au CREST et professeure associée à l’École polytechnique, est intervenue dans l’émission Entendez-vous l’éco ? sur France Culture.
L’épisode intitulé “Accords commerciaux : que reste-t-il à négocier ?“, revenait sur l’accord commercial conclu cet été entre Donald Trump et Ursula von der Leyen, et interrogeait plus largement les enjeux des négociations transatlantiques. Aux côtés de François Chimits (Institut Montaigne) et de Sylvie Matelly (Institut Jacques Delors), Béatrice Cherrier a apporté un éclairage original en explorant la fabrique de l’expertise économique.
L’apport de l’histoire de l’économie au débat public
Dans son intervention, Béatrice Cherrier a montré comment l’histoire des sciences économiques permet de mieux comprendre la manière dont les modèles et outils mobilisés par les économistes influencent les politiques publiques. Elle a notamment souligné l’importance de prendre en compte les contraintes méthodologiques et techniques qui orientent les choix des experts – par exemple la recherche de modèles “tractables”, c’est-à-dire plus faciles à manier et à résoudre, mais parfois au prix d’une simplification excessive des réalités étudiées.
En mettant en perspective l’évolution de la pratique économique au cours des dernières décennies, Béatrice Cherrier a rappelé que les instruments utilisés aujourd’hui pour analyser les accords commerciaux ne sont pas neutres : ils sont le produit d’une histoire intellectuelle, institutionnelle et technologique qui mérite d’être interrogée.
Un regard CREST sur les enjeux contemporains
La participation de Béatrice Cherrier illustre le rôle actif des chercheurs et chercheuses du CREST dans le débat public. À travers ses travaux, elle contribue à éclairer les grands enjeux contemporains en montrant comment l’économie se construit à l’intersection des idées, des pratiques et des contextes institutionnels.
Cette intervention s’inscrit dans la mission du CREST : produire une recherche de pointe en économie et en sciences sociales, tout en nourrissant la réflexion collective sur les politiques publiques et les grands défis de nos sociétés.
Réécouter l’émission sur France Culture ici.
Our PhD Students on the Job Market – A New Chapter Begins
Every year, a new generation of PhD students completes their journey at CREST and takes their next steps in academia or beyond. This year, several of our doctoral candidates have successfully defended their dissertations and are now preparing to join leading universities and research institutions worldwide.
Their years at CREST have been marked by rigorous research, intellectual curiosity, and strong community ties. We are proud of their achievements and the new perspectives they will bring to their future institutions.
Below, you will find their portraits. By clicking on each photo, you can discover their research, their journey, and their plans for the future.
We warmly congratulate them and wish them all the best in this exciting new chapter!
Marion Brouard
Claire Leroy
Federica Meluzzi
Thomas Monnier
When Managers Choose: Gender Disparities in Employer Training Provision
CREST Working Papers Series No. 2025-10
by Marco Caliendo, Deborah A. Cobb-Clark, Katrin Huber, Harald Pfeifer, Arne Uhlendorff and Sophie Wagner
Unpacking Rising Inequality: The Roles of Markups, Taxes, and Asset Prices
CREST Working Papers Series No. 2025-09
by Stéphane Auray, Aurélien Eyquem, Bertrand Garbinti and Jonathan Goupille-Lebret