Monday assorted links
2. “Risk of myocarditis is higher after Covid infection than after vaccine.” For young people, yup.
3. Claims about Tokyo’s train system. Princeton job market paper.
4. Matt Y. on the game theory of some of the Democrats conceding. And thoughts from Sam Stein.
5. Japanese buzzwords of the year?
6. Only five countries have no Swiss citizens living there. It seems it would be more efficient for that number to be higher?
7. The #1 country song is AI-generated?
8. Efforts toward genetically-engineered babies (WSJ). And the “fertility awareness” movement (NYT).
More From Less: Optimizing Vaccine Doses
During COVID, I argued strongly that we should cut the Moderna dose in order to expand supply. In a paper co-authored with Witold Więcek, Michael Kremer and others, we showed that a half dose of Moderna was more effective than a full dose of AstraZenecs and that doubling the effective Moderna supply could have saved many lives.
It’s not just about COVID. My co-author on the COVID paper, Witold Więcek, has found other examples where a failure to run dose optimization trials cost lives:
Take the human papillomavirus (HPV) vaccine. For years after its introduction, countries administered it as a three-dose series. Then additional evidence emerged; eventually, a single dose proved to be non-inferior. This policy shift, driven by updated World Health Organization (WHO) guidance, has been a game-changer—massively reducing delivery costs while expanding coverage in low- and middle-income countries (LMICs). But it took 16 years from regulatory approval to WHO recommendation. Had this change been implemented just five years earlier, the paper estimates that 150,000 lives could have been saved.
Knowing the potential for dose optimization should encourage us to take a closer look at what we can do now. Więcek points to two high-opportunity projects:
- The pneumococcal conjugate vaccine (PCV) is already Gavi’s top cost driver, consuming $1 billion of its 2026–2030 budget. But new WHO SAGE guidance, from March 2025, suggests that in countries with consistently high coverage (≥80–90 percent over five years), either one of three shots could be dropped, or each of the three doses can be lowered to 40 percent of the standard dose. While implementation requires sufficient epidemiological surveillance, its cost would be offset by significant savings in vaccine costs: a retrospective analysis suggests that for the 2020–25 period this approach could have led to as much as $250 million in savings.
- New tuberculosis vaccines, currently in phase 2–3 trials, are another high-impact example. Given initial promising results, a future vaccine could prove highly effective, but may also become a significant cost driver for countries and/or Gavi—and optimization may prove highly beneficial both in terms of health and economic value.
Witold’s new paper is here and here is excellent summary blog post from which I have drawn.
Addendum: See also my paper on Bayesian Dose Optimization Trials and from Mike Doherty Particles that enhance mRNA delivery could reduce vaccine dosage and costs.
How has Japan managed its debt ratio?
They have been using an implicit sovereign wealth fund, even in light of rising debt levels:
Since 2012, the social security fund has increased its exposure to riskier assets. In 2013, a government panel recommended a major reallocation of government-run pension funds into higher-yield investments (Hoshi and Yasuda 2015). Following this shift, three-quarters of public pension fund assets were allocated equally across three categories of risky assets: domestic equities, foreign equities, and foreign bonds (each at 25 percent). Over the past decade, these investments have generated strong realized returns, boosting the net asset position of public pension funds from around 40 percent of GDP to over 60 percent of GDP.
And this:
In fact, Japan’s net liabilities decreased over the past ten years from 118.4 percent to 77.6 percent. However, these gains have come from taking risks — in particular, the risks of duration mismatch and currency mismatch.
That is from a new JEP article by Yili Chien, Wenxin Du, and Hanno Lustig. Good work, but of course that makes Japan correspondingly vulnerable in the event of a major global equities downturn.
In defense of Schumpeter
Factories of Ideas? Big Business and the Golden Age of American Innovation (Job Market Paper) [PDF]
This paper studies the Great Merger Wave (GMW) of 1895-1904—the largest consolidation event in U.S. history—to identify how Big Business affected American innovation. Between 1880 and 1940, the U.S. experienced a golden age of breakthrough discoveries in chemistry, electronics, and telecommunications that established its technological leadership. Using newly constructed data linking firms, patents, and inventors, I show that consolidation substantially increased innovation. Among firms already innovating before the GMW, consolidation led to an increase of 6 patents and 0.6 breakthroughs per year—roughly four-fold and six-fold increases, respectively. Firms with no prior patents were more likely to begin innovating. The establishment of corporate R\&D laboratories served as a key mechanism driving these gains. Building a matched inventor–firm panel, I show that lab-owning firms enjoyed a productivity premium not due to inventor sorting, robust within size and technology classes. To assess whether firm-level effects translated into broader technological progress, I examine total patenting within technological domains. Overall, the GMW increased breakthroughs by 13% between 1905 and 1940, with the largest gains in science-based fields (30% increase).
That is the job market paper of Pier Paolo Creanza, who is on the market this year from Princeton.
*Violent Saviors*
That is the new William Easterly book, and the subtitle is The West’s Conquest of the Rest. I liked this book very much, but found the title and also book jacket and descriptions misleading. I think of this work as a full-throated examination and study of the classical liberal anti-imperialist tradition. We have been needing such a thing for a long time. It is not that I expected Easterly to be poorly informed, but it amazes me how well he knows this material from a historical point of view. A lengthy (and good) discussion of E.D. Morel!
So recommended, and here’s hoping these traditions find some new legs and less crazy adherents.
Sunday assorted links
1. Farmers’ Almanac will cease publication.
2. Econ history job candidates this year, a list.
3. How an econ job market candidate should maximize his or her LinkedIn profile.
4. “Mamdani is under fire for charging people $13 per beer at his ‘victory party’.”
5. Burn-Murdoch covers Noy and Rao on polarizing media (FT).
Educational for-profit charter schools do worse in Sweden
I estimate the long-run earnings impacts of for-profit and non-profit charter high schools in Sweden. Since the 1990s, privately managed schools have expanded dramatically—driven entirely by for-profit providers—and now enroll nearly half of urban high school students. Unlike in many other settings, there are no schools operating outside of the public system: all schools rely on equal public funding, cannot charge top-up fees, and are subject to the same regulation. Using a combination of value-added and regression discontinuity methods, I find that charter school attendance reduces long-run earnings by 2% on average—comparable to the returns to half a year of schooling in similar settings. For-profits generate these losses by hiring less-educated, lower-paid teachers, consistent with concerns around cost-cutting. By contrast, non-profits reduce earnings by specializing in arts programs: conditional on such specialization, they perform as or even better than public schools. In a discrete choice framework using rank-ordered school applications, I show that students’ preferences are weakly related to schools’ earnings impacts. Most of the for-profit market share is explained by student demand for attractive locations and study programs, presenting a trade-off between satisfying short-run demand and boosting long-run economic outcomes.
That is the job market paper from Petter Berg, from Stockholm School of Economics.
Housing costs and fertility
Many developed countries face low and falling birthrates, potentially affected by rising costs of housing. Existing evidence on the fertility-housing cost relationship typically uses geographic variation (raising selection issues), neglects unit size, and says little about policy. To progress on these fronts, I first specify a dynamic model of the joint housing-fertility choice allowing choices over location and house size, estimated using US Census Bureau data. I extend ‘micro-moment’ techniques (Petrin, 2002; Berry et al., 2004a) both to circumvent data constraints and to incorporate heterogeneous residuals, which can prevent misspecification. Housing choice estimates confirm a Becker quantity-quality model’s predictions: large families are more cost-sensitive, and so rising housing costs disincentivize fertility. To study the causal effect of rising housing costs on fertility, I vary them directly within the model, finding that rising costs since 1990 are responsible for 11% fewer children, 51% of the total fertility rate decline between the 2000s and 2010s, and 7 percentage points fewer young families in the 2010s. Policy counterfactuals indicate that a supply shift for large units generates 2.3 times more births than an equal-cost shift for small units: family-friendly housing is the more important policy lever.
That is from Benjamin K. Couillard, a job market candidate from University of Toronto.
Should USG support a 50-year mortgage?
More “affordability” from Trump!? From GPT-5:
Broad, government‑backed 50‑year mortgages would likely lower monthly payments but raise house prices, slow equity build‑up (and raise default risk in downturns), and increase interest‑rate risk in the financial system. As a general affordability policy for the U.S., that’s a poor trade‑off. If used at all, a 50‑year term should be tightly targeted (e.g., to loan modifications or to newly built homes only), not adopted wholesale for new purchases…
In the short run, sellers and incumbent owners capture much of the benefit via higher sale prices; first‑time buyers face higher entry prices…
Here is the whole answer. Albania has the right idea!
The first human arrivals in the New World may have sailed from northeast Asia
The first people to migrate to North America may have sailed from north-east Asia around 20,000 years ago. Experts have argued that prehistoric people in Hokkaido, Japan, used similar stone tools to those later found in North America, and suggest that seafarers may have travelled to the continent during the last ice age, bringing this stone technology with them. This adds weight to the theory that the first Americans arrived much earlier than previously thought.
And:
“By [around 30,000 years ago], Upper Palaeolithic seafarers were using sea-going vessels to access some of the outer islands in the Japanese archipelago … and were capable of negotiating the Kuroshio Current, one of the fastest in the world,” Davis and his colleagues write in their paper, published in October in the journal Science Advances. “This suggests that such experienced seafarers may also have been capable of handling adverse Pacific coastal currents.”
Nonetheless, the team also suggest that the journey could have happened at a much slower pace. In this reconstruction, the prehistoric seafarers gradually followed a route along the Pacific coast.
Here is the full story. I have long wondered why, every now and then, in Japan I see a person who looks a great deal like a “Native American.”
Saturday assorted links
1. Zvi (NN) on my podcast with Sam Altman. I will note that GPT-5 is very good at picking out restaurants for me in northern Spain, and Neruda you have to read in Spanish, otherwise it is lame.
2. Peter Thiel on young people and socialism (Free Press).
3. Is the Heritage Foundation imploding?
4. Fertility job market papers.
5. Iguana advisory for Florida.
6. The full twenty minute Sydney Sweeney GQ interview is worth watching. Few books about sociology are this valuable. And memed, about free trade.
My podcast with Deutsche Bank
This was at first for a recent private event, now they have released the session. First I am interviewed, and then there is audience Q&A. Here is the Spotify link.
Emergent Ventures India, 12th cohort
Harish Ashok, 16, received his grant to build a multi-purpose rover.
Dev Patel, economist, received his grant to expand his method combining machine learning and geophysics to detect and forecast floods across Indian villages.
Saurabh Chandra, Pranay Kotasthane, and Khyati Pathak received their grant for Puliyabaazi Hindi Podcast, to expand and develop articles and video formats in simple, conversational Hindi.
Vishrant Dave, Ayush Ranjan and Prateesh Awasthi received their grant for Armatrix, hyper-redundant robotic arms for inspection and maintenance in hard-to-reach and hazardous industrial environments.
Akhil Reddy K received his grant for Livestockify, to develop solar-powered IoT sensors for real-time poultry disease and health monitoring.
Mohil Ahuja, 19, received his grant to develop a low-cost algae-based air purification system addressing indoor pollution.
Reivanth Kanagaraj received his grant for ColourCryption, to create low-cost anti-counterfeiting solutions using fluorescent inks.
Kaviraj Prithvi, 23, received his grant for uDot, to build a tactile display enabling blind students to study STEM.
Tawheed Rahman, highschooler, received his grant to build a low-cost prosthetic robotic arm.
Keya Shah, 22, received her grant to develop a prosthetics solution in Bangalore.
Sanjay Ganguli received his grant to acquire equipment for documenting wildlife stories from India.
Avhijit Nair, 26, received his grant for HydroPlas Tech, to produce graphene from waste plastic.
Rain Rejius received his grant for TRIPd, to develop a wearable revolutionizing personal temperature control through thermoreceptors.
Pragyaan Gaur, 18, received his grant to build technology reducing industrial sulfur dioxide emissions.
Wajih ur Rehman received his grant to develop an aerosol-technology-based solution to curb air pollution in Pakistan.
Rakshith Aloori, 25, received his grant to build desalination machines solving the water crisis.
Prashansa Tripathi, doctoral student at IIT Jodhpur, received travel and conference support to attend the cognitive neuroscience skills training program at Cambridge University.
Those unfamiliar with Emergent Ventures can learn more here and here. The EV India announcement is here. More about the winners of EV India second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, and eleventh cohorts. To apply for EV India, use the EV application, click the “Apply Now” button and select India from the “My Project Will Affect” drop-down menu.
And here is Nabeel’s AI engine for other EV winners. Here are the other EV cohorts.
If you are interested in supporting the India tranche of Emergent Ventures, please write to me or to Shruti at [email protected].
TC again: I thank Shruti for preparing this blog post, and for all the work behind it!
Affordability sentences to ponder
Two books I hope you do not mood affiliate against
The firtst is Laura K. Field, Furious Minds: The Making of the MAGA New Right.
The author chronicles the history of the “New Right” from a left-wing perspective, and often in ways that non-Trumpers also will find objectionable. Still, the book has plenty of facts and substance, and it is the best history of this group I know of. There is plenty of biography and group identification in here, so it serves as a guidebook.
The second is Mahmood Mamdani, Slow Poison: Idi Amin, Yoweri Museveni, and the Making of the Ugandan State. I ordered this one before I knew who wrote it, namely Papa Mamdani. Again, there is plenty you can object to here, but it is an actual (partial) history of Uganda, interwoven with autobiography. The author actually tries to explain to you what was going on, rather than writing to “fill a gap in the literature,” or whatever. Too bad his actual views are so objectionable — Papa Mamdani, Uganda never had neoliberalism! Yet I am glad I bought it and will continue reading it, because it fills in many pieces of the story, most of all for the Ugandan campaigns against Israelis, the British, and Indians.
And there you go.