Alex Hsu 許家樺

I was the jr. guy presenting in a random fiscal policy session. Chris was the keynote. He walked in middle of my presentation. Sat down. Asked some questions and gave feedback. I was sweating. He was just kind. I will never forget that interaction for the rest of my career.

Building on last year's success, the Dept of Economics at @MiamiHerbert @univmiami will host the Miami Macro 2026 Conference “Monetary and Fiscal Policy in a New Era” on April 24, 2026. Join us in Miami! Submission deadline is March 15. See full CFP here: noahwilliams.xyz/conferences/mf…

Call for papers: "Macroeconomic Policy Perspectives". 2026 Conference Theme: The Long-Run Implications of Deglobalization sites.google.com/view/mppconfer…

🤔

@Noahpinion 100%

I haven't flipped from being an AI optimist to being an AI doomer. But I am definitely more worried about AI risk than I was a few months ago -- especially about bioterror. noahpinion.blog/p/updated-thou…

📢📢New paper alert. Looking at 3 centuries of US and UK data, we conclude that r is much lower than g during wars, because of a surge in surprise inflation and financial repression, but not in peacetime. dx.doi.org/10.2139/ssrn.6…

In this blog post, @RWacziarg and I explain why the EU's 90bn Euro Ukraine deal in December 2025 was really a bad deal for Europe by moving the EU closer to a half-baked fiscal union. open.substack.com/pub/thetwocent…

Adrien Auclert will present "New Keynesian Economics with Household and Firm Heterogeneity" in this month's VSME which we at the @sffed jointly organize with @cepr_org. Join us on Thursday at 11am ET for Adrien's talk and a Q&A session! cepr.org/events/event-s…

🚨Break News!🚨 GT FINANCE IS HIRING! We are looking for a tenure track assist prof. The position starts in Aug 2026. We will review applications on a rolling basis. Flyout decisions will be made early Feb. Interested candidates should apply here: careers.hprod.onehcm.usg.edu/psc/careers/CA…

Japan is an interesting case in a lot of ways. It has a ton of domestic debt (and significant domestic financial assets) which generates heated concerns about its solvency/ ability to manage higher rates. But it is also a massive global creditor -- 1/

@BachmannRudi 😂

We love Econometrica. The editors of Econometrica are great people. Totally incompetent, but we love them. Metron always rejects my submissions, but then he texts me: Oh, Rudi, ohlala, submit your papers to Econometrica. Next time, I will desk accept. I have the best papers.

@alexolegimas I was just thinking earlier in the week how AI makes us better communicators and teachers. Adding interactive media in lecture slides is no longer a chore.

One of the most promising uses of AI is creating a more robust protocol for science. Imagine if every paper came with a a transparent, interactive appendix where you can see the robustness and reliability of the results in real time. Automatic robustness to diff specifications, instant replication, continuous updating as new data is available. It is possible to do all this with the tools we have *now*. I know @ahall_research is working on this, as is @PaulLitvak.

@JesusFerna7026 🤣

@MGoFinance I should get a commision from Anthropic 😊

Ok, I finally accepted reality and upgraded to the $100-a-month Claude plan. The usage limits were getting on my nerves, and for my academic research, Claude is working noticeably better than ChatGPT. ChatGPT, though, still wins hands down for help with X posts or picking a movie to watch. Who would have told me just a few years ago that I would be spending more every month on AI tools than on my phone plan or my TV streaming services? At this rate, my AI bill is starting to look uncomfortably close to my monthly car lease payment. This is a new world!

Highly recommended! "The future of the Fed: Central bank independence and fiscal dominance," speech by Janet L. Yellen. "What would keep the U.S. out of fiscal dominance? First and foremost, this requires credible medium-term fiscal adjustment—not abrupt austerity, but a believable path that stabilizes debt/GDP; for example, through gradual changes to taxes and entitlements or reforms that tilt growth and productivity higher. Unfortunately, however, the revealed preference of both parties has been toward deficit-increasing policy." brookings.edu/articles/remar…

Taiwan's surplus is going through the bloody roof $15b in December works out to $175b a year annualized the surplus in 2024 was already large -- yet it was "only" around $50b AI bubble or not, that is a ton cash 1/

Over the years, I have actively participated in the economic policy debate in Spanish and written a fair amount on the topic (including many papers and several books!). Some of these issues go beyond purely local interest and are relevant, with only minor changes, for other countries in Western Europe and Latin America. I have always wanted to translate some of this work into English (if only to reach a wider audience), but until recently the cost was prohibitive. Thanks to AI, that cost has now fallen by roughly two orders of magnitude. Yesterday, I circulated a short policy paper I wrote over the Winter Break in Spanish arguing that it is far more useful to think about the sustainability of pay-as-you-go social security systems in terms of their internal rate of return (IRR) than to focus on cash flows, as much of the debate tends to do. The paper went viral, and several non-Spanish economists expressed interest. This morning, I translated it into English with the help of AI and made some light adaptations. I did not spend a great deal of time polishing every detail, but I think it is still well worth reading: sas.upenn.edu/~jesusfv/Pensi… The punchline will not be new to anyone who has read Samuelson’s (1958) classic paper, but it bears repeating. The key to the sustainability of a pay-as-you-go social security system is that the IRR received by participants must equal the growth rate of the system’s revenues. Once you think in these terms, almost everything else becomes secondary. Lower fertility simply implies a lower growth rate of revenues. Along the same lines, higher wages do not necessarily help the system if the IRR is already too high. In fact, they can make things worse, because an excessive IRR is then paid over a larger base. Somewhat surprisingly, when I explained this point to several excellent economists, many told me they had never thought about it this way. What actually helps a pay-as-you-go system is faster wage growth, because it raises the growth rate of revenues. It is all about the derivative, not the level. The effects of immigration are also much more nuanced than is often assumed. If the IRR is too high, bringing in additional immigrants may worsen the system’s present discounted balance, even if it improves the current cash-flow position. As always, comments are welcome. I may write something longer in the future, and I would welcome any suggestions. P.S. I write differently in Spanish than in English. Do not be surprised if the paper reads somewhat differently from my work originally written in English. Personally, I think I write much better in Spanish, but that style does not always translate cleanly.

@alexolegimas Absolute game changer…

I, for one, am delighted! I’ve never been more excited about research (with a good degree of trepidation about the broader economic impact).

Let me draw out one point in China's q3 balance of payments (a rather subtle one) -- namely the large sales of Chinese bonds by foreign investors in q3. (the red bar in the graph) 1/