Lars Peter Hansen

In 2024, Eric Leeper and Tao Zha organized a conference honoring Chris’s legendary career. Here is a photo of Chris with some of his students. Thank you for everything you gave to our profession and to us. Rest in peace, Chris.

Reminder: The applications deadline for the 2026 @MFRProgram Summer Session for Young Scholars held this August is on this March 1, 2026. Interested PhD students pursuing research at the intersection of macroeconomics and finance should apply by this Sunday. More information here:

Applications are still open for the 2026 MFR Summer Session for Young Scholars to be held August 4-7, 2026! Join a vibrant community of young researchers and distinguished faculty. Deadline is March 1st. Learn more and apply here: tinyurl.com/me93dn6y @UChicago #EconTwitter

Applications are open for the 2026 @MFRProgram Macro Finance Research Program Summer Session for Young Scholars, taking place at the Gleacher Center in downtown Chicago on August 4–7, 2026. Young scholars are encouraged to apply by March 1, 2026. Learn more and apply here: tinyurl.com/35rde2j8 @UChicago #EconTwitter #macroeconomics @BeckerFriedman

Reminder: Applications for the @MFRProgram 2026 Modeling Climate-Dynamics Workshop for Young Scholars are due February 1, 2026. The workshop will be held at @UChicago on May 27–29, 2026. Details: tinyurl.com/2ee2cymz #EconTwitter #climatemodeling #climatechange #macroeconomics @BeckerFriedman

XXVIII Workshop in Intl Econ & Finance Rio de Janeiro (EPGE-FGV): July 19-20, 2026 Submission deadline: March 1 Keynote speaker: Lars Hansen @UncertainLars Website: utdt.edu/ief-workshop Submission form: tinyurl.com/submit-rio Scientific Committee: Fernando Alvarez, University of Chicago Aloísio Araujo, Fundação Getulio Vargas João Ayres, Inter-American Development Bank Karen Lewis, Wharton School, UPenn Andy Neumeyer, Universidad Torcuato Di Tella Jesica Roldan Peña, CAF - Banco de Desarrollo Guillermo Vuletin, The World Bank Partners: @EconomiaDiTella @voxlacea @ElBid @EPGE_FGV @agenfacaf @BancoMundialLAC

This article makes some strong points about climate policy uncertainty and the risks of a false pretense of knowledge. I only wish the academic references were more up to date: #climatechange #policyuncertainty theatlantic.com/science/2026/0…

The first-ever Chapel Hill-Copenhagen Conference on Macroeconomics and Deep Learning will take place on September 3+4 in beautiful Chapel Hill dlmacro-conference.vercel.app! We are very honored to have @UncertainLars (@MFRProgram, @BeckerFriedman, @UChicago) as our keynote speaker.

@jmwooldridge @usuartsci Nice of you to remind me of this!

@UncertainLars @usuartsci I remember that your father was a key member of the Biochemistry faculty at MSU back in the day, and that you spent many formative years in East Lansing. I guess you know there's an MSU award named after him: bmb.natsci.msu.edu/about/awards/r…

Grateful to see my dad’s long commitment to biochemistry at Utah State University live on. @usuartsci

R. Gaurth Hansen Assoc Prof Ryan Jackson, with his students and colleagues, publishes new findings about #CRISPR system that could lead to single diagnostic test for #COVID, #Flu, #RSV @USUAggies @USUPres @research_usu @usuchemistry

As I close out my first year of posting on X, I looked at the post that resonated most with readers in 2025 to learn what I could do better. Since I post in English and in Spanish, today I will comment on the readers’ ten favorites in English, and tomorrow on the readers’ ten favorites in Spanish. 1️⃣ The most viewed post, by far, and also the most important one: my slide deck on the demographic future of humanity, with over 1.1 million views: x.com/JesusFerna7026… Nothing will shape the next 50 years as much as the incredible drop in fertility that we have seen worldwide over the last 10 years. I cannot insist on this fact enough. Everything else will be second order. I really need to find the time to write a book on this. 2️⃣ Next, a personal favorite: Ten statements that demonstrate that someone does not understand modern economics or what an equilibrium is, and that you can safely ignore everything else they say, with 617k views: x.com/JesusFerna7026… I like this post so much that I now use the definition of recursive competitive equilibrium as my banner photo. It was also a lot of fun, but it is important to say it clearly and loudly: “heterodoxy” in economics is nothing but a lame excuse for low performers. 3️⃣ Coming back to fertility: Total Fertility Rate (TFR) in the Americas: A Quiet Revolution, with 522k views: x.com/JesusFerna7026… Did you know that Latin America, as a whole, now has a fertility rate below that of the U.S.? You probably did not. In fact, some of the lowest-fertility countries in the world right now are in Latin America, such as Chile and Colombia. 4️⃣ Industrial policy: Can industrial policy work? Yes. The East Asian experience shows it can (at least partially). But its success rests on a key condition: labor control, with 423k views: x.com/JesusFerna7026… I am nearly done with a paper making this point more formally. But the punchline is simple: if you are going to promote industrial policy, remember that you need to screw up the workers. Labor control is a necessary condition (although not sufficient) for its success. From my perspective, a compelling reason to avoid industrial policy. 5️⃣ An example of modern economic theory: I discuss a great paper by Simone Cerreia-Vioglio, @UncertainLars, Fabio Maccheroni, and Massimo Marinacci, “Making Decisions Under Model Misspecification,” published in the Review of Economic Studies a few months ago. This one got 340k views: x.com/JesusFerna7026… 6️⃣ This one was nice: a vindication of analytic Marxism and its tradition of rigor, with 304k views: x.com/JesusFerna7026… The best part? Showing that analytic Marxists know how to define equilibrium. 7️⃣ More fertility: sponge cities, with 272k views: x.com/JesusFerna7026… Guess what? Population decline will not be uniform across space, and a few cities will accumulate more of the remaining population. I have seen this in Asturias, where my family comes from. The consequences are tremendous. 8️⃣ Teaching content: the posts where I shared the slides of my undergraduate global economic history course this fall were a constant favorite. This slide deck, x.com/JesusFerna7026… on the cradle of modernity, was particularly successful, with 228k views. 9️⃣ This one matters a lot: the contribution of individuals to the welfare state versus the taxes they pay over the life cycle, with 206k views: x.com/JesusFerna7026… Why? Because when we compute an individual's net contribution to the budget, we need to look at the present discounted value over their entire life, not just at a single point in time. This, for example, changes how one should assess the fiscal impact of migration. 🔟 Finally, a post related to Spain, with 194k views: x.com/JesusFerna7026… The most important policy decision of my lifetime was taken around 2012–2015: whether Spain should remain in the euro or leave. I am immensely proud that I made the right call in real time: stay, no matter what, stay: elpais.com/elpais/2012/05… When several prominent members of Rajoy’s government were toying with the idea of leaving the euro, Tano Santos, @lugaricano, and I wrote an op-edmaking it clear that Spain’s commitment to the euro was non-negotiable. The experience of Brexit has since made it clear that, as hard as staying in the euro was, the alternative would have been two orders of magnitude worse. Those who called for Spain to leave the euro were beyond wrong. I am, of course, leaving out many other posts that I enjoyed a lot and am very proud of. Tomorrow: the readers’ favorites in Spanish.

Applications are now open for the @MFRProgram 2026 Modeling Climate-Dynamics Workshop for Young Scholars, held at the University of Chicago on May 27–29, 2026. Interested young scholars should submit applications by February 1, 2026. Learn more here: tinyurl.com/2ee2cymz   @UChicago #EconTwitter #climatemodeling #climatechange #macroeconomics @BeckerFriedman

USU undergrad researcher, URCO grant recipient and Hansen Life Sciences Retreat presenter Josh Westhora is investigating how to protect crops from insect pests. He presents to Utah legislators in Feb. 2026. @UncertainLars @usuchemistry usu.edu/today/story/fr…

Dinner with the Fama-Miller Center and Macro Finance Research Predocs. Huge thanks to Professor Yueran for organizing, and to Professor @UncertainLars and his wife, Grace, for joining us despite busy schedules. A lovely evening and not a single derivation requested.