Jesús Fernández-Villaverde
@JesusFerna7026
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Howard Marks Presidential Professor of Economics at the University of Pennsylvania and John H. Makin Visiting Scholar at the AEI. All opinions are my own.
Haverford, PA
Joined June 2024
👋 New to this feed? Here’s an introductory post to help you navigate what I share. 🧵 If a post is in English, it likely concerns economics. My main areas of interest (not necessarily those where I publish the most) include: 1️⃣ Demographics & Population Economics. Quick
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I gave a reading recommendation to a student that, as we enter a long weekend when some might have free time for reading outside the beaten path, I thought could be worth sharing: The Raven of Zurich: The Memoirs of Felix Somary. The student was intrigued by a passing remark I
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President Trump is right. To stay ahead in the global AI race, America needs a unified federal framework. One that promotes innovation without overbearing regulation. A smart, cohesive national policy will ensure that American ingenuity leads the world in the age of A.I.
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Very happy to see my paper “How substitutable are the classical and radical right?” with Carlos Sanz (at the Banco de España and CEMFI) published in the Journal of Public Economics. The paper addresses a simple question: take a party of the classical right (e.g., CDU in Germany
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Otra cifra llamativa del último barómetro del CEO: entre los mayores de edad con ciudadanía española residentes en Cataluña, el 57% tiene el español como lengua primaria y el 35% el catalán. Si añadimos a la población residente sin ciudadanía y a los menores de 18 años, el
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Un amable lector, @javiermcanto, me comenta que acaba de publicar este artículo: Aliança Catalana and Vox in Catalonia: united in nativism, divided by the nation https://t.co/LUwI3ashSL Para quienes piensen que los movimientos de voto entre Vox y AC son raros. Para mí es
tandfonline.com
Radical right nativist parties have gained ground across Europe in recent decades. However, a key unanswered question is how these parties adapt in contexts marked by the centre–periphery cleavage ...
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Gap x World, bridging the gap between humans and technology. Live @Gap Chestnut Street, San Francisco.
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El último barómetro de opinión política del CEO ha incendiado X hoy. Hay muchas cosas interesantes en el mismo, pero para mí una de las más destacables es la página 76 del dossier de prensa: la posición sobre la independencia de Cataluña por partido. De los cuatro partidos
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As someone whose most-cited work leans heavily on third-order Taylor expansions, I must report that my weekend has suffered a severe negative shock 🤣🤣🤣 That said, without third-order terms it becomes genuinely hard to talk about time-varying risk… so alas, the expansions
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My dear colleague at Penn, @HanmingF, has just published a new edited volume, “The Arch of the Chinese Economy.” Hanming shared an early draft with me, and the content is superb. In a landscape overflowing with uninformed commentary about China’s economy, this book stands out as
The book “The Arc of the Chinese Economy" (co-edited with Marshall Meyer) is now available at: Cambridge University Press (Discount code: TAC25) https://t.co/Tdkx0Z0WtH Also at Amazon: https://t.co/KM09F13iIC for immediate shipping.
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Este post ha debido de tocar una fibra muy delicada, porque en las últimas horas ha aparecido el equipo de opinión sincronizada (EPO) para dejar su habitual colección de comentarios chorras. La entrada del EPO es inconfundible por dos señales: 1) La calidad intelectual de los
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I have an important update about this: we are looking to fill out 5 senior slots and 3 junior slots. Please, apply and reach out if interested! Or help me to spread out the news! @HannoLustig @luigi_bocola @JonSteinsson @IvanWerning @glviolante @JesusFerna7026 @LudvigsonSydney
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Los que tengo en el Kindle. Principia iuris y Garantismo penal los tengo en papel.
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Yo estudié la licenciatura de Derecho. Aunque nunca he ejercido, recuerdo con absoluta nitidez algunas clases y las lecciones de varios profesores. En Derecho penal, parte especial, de tercero, nos dio clase una fiscal (lo siento, no recuerdo su nombre). Un día, hablando de las
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Muchos lectores han respondido a mi entrada de ayer sobre el gasto social y los impuestos por edad diciendo: “Esto es exactamente lo que pasa con un sistema de reparto; no me sorprende ni me preocupa”. Sí, es cierto que este es el patrón básico en un Estado del bienestar
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I forgot to add that this exercise is inspired by a similar exercise recently done for France.
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A coauthor of mine, @Jongonzlz, just computed age-indexed per-capita social spending and taxes for Spain. The figure below shows the results (any LLM can translate the axes if needed). Why should you care? Because the broad patterns apply to most Western countries. This is a
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🧵 On learning rates in #MachineLearning and #DeepLearning 1/7) I taught gradient descent (GD) yesterday, and there was confusion about how the learning rate affects stability and convergence. I also see this come up in talks, so here is a quick thread to clarify it.
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Very thankful to the Virtual Israel Macro Meeting (@vimacro_org) for inviting me to present today some of my recent work on “Deep Learning for Solving Economic Models.” The slides are here: https://t.co/No0aFSAx8k And the paper: https://t.co/pSOQQRhC9Z Let me emphasize that
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Last week, I reposted a very nice visualization by @alec_helbling showing how a one-dimensional representation of the data can be terrible, while a two-dimensional one reveals the true structure immediately. As many readers pointed out (and as I elaborated in a follow-up post),
Many dimensionality reduction algorithms share a few central principles. 1. Construct a graph that captures the data's local structure 2. Measure "geodesic" distances between points using the graph 3. Project the points to a lower dimension while preserving these distances
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During my lectures last week at the ECB and the Bank of Spain on deep learning, I realized that many people in economics and econometrics often overlook the fact that what constitutes a good representation of the data (the topic of my previous post) depends entirely on the task
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Yesterday, I gave the keynote address at the Bank of Spain’s Economics of Artificial Intelligence conference on “Deep Learning in Economics: A Geometric Interpretation.” The central point of my talk was that deep learning succeeds in economics because it offers a constructive
Data often lie on a low-dimensional manifold embedded in a high-dimensional space. But these manifolds are often highly non-linear, making linear dimensionality reduction methods like PCA insufficient. This has motivated the development of non-linear dimensionality reduction.
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This week I’ll be lecturing at the ECB on deep learning. More than ever, I plan to emphasize the importance of soft inductive bias, double descent, and benign overparameterization—topics I’ve discussed in many previous threads. These three closely related phenomena compel us to
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