Month: October 2025
Claims about polygyny
The title of this piece is “High rates of polygyny do not lock large proportions of men out of the marriage market.” I believe further investigation is warranted before drawing such conclusions, but here is the abstract:
Social scientists often assume that when men can marry multiple wives (polygyny), many other men will be unable to marry. Versions of this assumption feature prominently in theories of civil war, the evolution of monogamy, and the incel movement. Using census data from 30 countries across Africa, Asia, and Oceania, as well as data from the historical United States, we find no clear evidence that polygyny is associated with higher proportions of unmarried men in society. Instead, high-polygyny populations often have marriage markets skewed in favor of men, and actually, men in high-polygyny populations usually marry more than men in low-polygyny ones. These findings challenge entrenched assumptions and inform debates on marriage systems, societal stability, and human rights.
That is from a recent paper by Hampton Gaddy, Rebecca Sear, and Laura Fortunato. At the very least, you hear the contrary story so often, and without firm documentation, that it is worth shaking the debate here a little bit.
Andrew wants new Singapore recommendations
From my email:
I will be in Singapore soon. Do you have any up-to-date recommendations? I notice there is this old post: https://marginalrevolution.com/marginalrevolution/2015/12/how-to-visit-singapore.html
Comments are open…
Wednesday assorted links
Where has beauty gone in the modern world?
From David Perell and Cultural Tutor, a preview of a longer film to come:
Share repurchases do not discourage investment
Theory tells us that, and the empirics tell us that too:
Our study examines the claim that share repurchases lead to reductions in real investments. Repurchase opponents argue that managers forego valuable investments to conduct opportunistic repurchases, while proponents argue that repurchases return excess cash to shareholders. We compare repurchasing firms’ real investments in capital expenditures, R&D, and employment to public and private non-repurchasing firms—holding constant their growth (i.e., investment) opportunity sets. Our results provide no support for the claim that repurchases lead to lower real investments. Consistent with these findings, we also show that financial analysts do not revise downward their capital expenditure forecasts following repurchases.
That is from a recent paper by Paul Brockman, Hye Seung (Grace) Lee, and Jesus M. Salas. You see the opposing argument in the media all the time, but it is wrong, wrong, wrong. As in “not correct.”
Via the excellent Kevin Lewis.
Black Veterans and Civil Rights After World War I
Nearly 400,000 Black men were drafted into the National Army during World War I, where they toiled primarily as menial laborers in segregated units. Leveraging novel variation from the WWI draft lottery and millions of digitized military and NAACP records, we document the pioneering role these men played in the early civil rights movement. Relative to observably similar individuals from the same draft board, Black men randomly inducted into the Army were significantly more likely to join the nascent NAACP and to become prominent community leaders in the New Negro era. We find little evidence that these effects are explained by migration or improved socioeconomic status. Rather, corroborating historical accounts about the catalyzing influence of institutional racism in the military, we show that increased civic activism was driven by soldiers who experienced the most discriminatory treatment while serving their country.
That is from Desmond Ang and Sahil Chinoy, newly accepted into the QJE. Are we so sure the postulated mechanism is the correct interpretation for the results here? Being in the military can have other intellectual influences too. Via Alexander Berger.
Tuesday assorted links
1. For different states, where the main immigrant group comes from.
2. NBA rookies do worse when they end up on very good teams.
3. Yale Budget Lab study claims AI is not having much of an effect on labor markets.
4. Twenty-five questions university presidents, provosts, and deans need to be asking themselves.
5. Is there a college radio revival?
6. Data centers have a great ratio of tax revenue brought in to electricity price boost.
7. The revolution in New Hampshire electricity policy (WSJ).
Singapore fact of the day
For every Singaporean who has left Christianity, about three others have become Christians.
About 3.2 in fact, if you look at the exact numbers. Buddhism in Japan and South Korea is being depopulated, also. Here is the Pew piece on defections from religions.
MR Podcast: Our Favorite Models, Session 1
The Marginal Revolution Podcast is back and this time Tyler and I discuss some of our favorite models or ways of thinking about the world. We begin with Spence on Monopolies, Harberger on Incidence and Solow on Growth. Here’s one bit:
TABARROK: You have an increase in the corporate tax. What happens?
COWEN: One lesson of the Harberger model is actually anything can happen. Who bears the burden? Is it capital, is it labor, or is it consumers? In the simplest versions of the model, what you have is both a substitution, capital versus labor in the taxed sector, and you have substitutions across sectors. You have a whole series of different effects. One of the first and simplest lessons from Harberger, which is really neat, but people just hadn’t gotten it before, is if you tax the corporate sector under a lot of reasonably general assumptions, the rate of return on capital goes down equally in both sectors, which to us is standard fare.
What will happen is capital flows out of the corporate sector into the noncorporate sector, that lowers the marginal rate of return on capital in the nontaxed sector, and simply the notion of capital can suffer in both sectors. Again, a revelation, maybe self-evident to us having written this principles textbook, but it shocked people. The partial equilibrium models never show that.
TABARROK: When you tax the corporations, you’re also taxing the mom-and-pops.
COWEN: And the nonprofits and whatever, wherever else the capital might flow.
TABARROK: Yes. This was one of the first useful applications of general equilibrium.
COWEN: That’s right. On that, it’s really held up. International affairs, one of the lessons is if you turn the other sector or add another sector that’s international, basically small economies cannot afford to tax capital at very high rates because so much of the capital will flow elsewhere.
TABARROK: Instead of it flowing to the noncorporate sector, it just flows out of the country.
COWEN: That’s right, which is like the other sector not affected by this particular tax. In 1962, a lot of small economies treated their capital very badly. Many still do, but there’s been a real revolution where even fairly statist economies—like the Nordics over time shifted to treating capital income pretty generously. Singapore would be another example. Again, it’s simple once you know it, but the Harberger model taught us that.
TABARROK: What about the labor margin?
COWEN: The debate since then has been how much of the tax is borne by capital and how much is borne by labor? On one hand, the Harberger model teaches you anything can happen. That’s useful intuitively. In fact, when you investigate it empirically, it’s what you would expect to happen that mostly happens. That is, capital does bear more of the tax than labor.
TABARROK: Labor bears a chunk.
COWEN: Yes. A typical estimate might be a third. There’s no free lunch from the point of view of labor. Furthermore, a lot of the capital is owned by labor through pension funds. If you take that into account, I don’t have an exact number for you, but I think it’s plausible to think labor might bear half the burden of the corporate tax. Again, you can show that pretty simply. The estimates are not exact, but just a big advance for economics. If you ask me, what ideas do I use all the time, that’s one of them.
The Harberger basic model, it doesn’t have land, but there’s the issue of what if you have three factors in the model, you would start with the Harberger model. If you’re a NIMBY who thinks there’s this kind of land monopoly in a city or land rents are very high because we stifle building, the incidence of a lot of taxes, even in general equilibrium models, can fall on the land for a city.
TABARROK: Yes, because the land can’t escape.
COWEN: That’s right.
TABARROK: As we say in the textbook, elasticity is equal to escape, right?
Here’s the episode. Subscribe now to take a small step toward a much better world: Apple Podcasts | Spotify | YouTube.
Who exactly is rigid again?
In an adversarial collaboration, two preregistered U.S.-based studies (total N = 6181) tested three hypotheses regarding the relationship between political ideology and belief rigidity (operationalized as less evidence-based belief updating): rigidity-of-the-right, symmetry, and rigidity-of-extremes. Across both studies, general and social conservatism were weakly associated with rigidity (|b| ~ .05), and conservatives were more rigid than liberals (Cohen’s d ~ .05). Rigidity generally had null associations with economic conservatism, as well as social and economic political attitudes. Moreover, general extremism (but neither social nor economic extremism) predicted rigidity in Study 1, and all three extremism measures predicted rigidity in Study 2 (average |bs| ~ .07). Extreme rightists were more rigid than extreme leftists in 60% of the significant quadratic relationships. Given these very small and semi-consistent effects, broad claims about strong associations between ideology and belief updating are likely unwarranted. Rather, psychologists should turn their focus to examining the contexts where ideology strongly correlates with rigidity.
That is from a new piece by Shauna M. Bowes, Cory J. Clark, Lucian Gideon Conway III, Thomas Costello, Danny Osborne, Philip E. Tetlock, and Jan-Willem van Prooijen. Via the excellent Kevin Lewis.
Emergent Ventures winners, 47th cohort
Vivek Kommi, 16, London, Extend healthy human lifespan by hacking the neuroimmune axis.
Adam Essemaali, northern Italy, 16, a new platform.
Rushil Kukreja and co-workers, northern Virginia, high school, devices to see through walls.
Sheehan Quirke, also known as The Cultural Tutor, London, work with David Perell, on why beauty has disappeared in the modern world.
Sambhav Baid, Singapore, measuring when antibiotics have stopped working.
Skyler Lee, Cumming, Georgia, high school, better app for language teaching.
Santiago Del Solar, Waterloo, Ontario, exoskeletons.
Daniel Remler, WDC, AI and diplomacy.
Jacob Neplokh, University of Chicago, political theory and the great books.
Kyle Redlinghuys, London, AI-enhanced pre-natal testing.
Paddy Corcoran and Sean Cahill, 16 and 17, Tipperary, app for TikTok and study.
Juan David Campolargo, Illinois, to write a book on universities and how to get the most out of them.
And here is Nabeel’s semantic search for previous EV winners.
Monday assorted links
1. Costco to sell GLP-1s at a significant discount.
2. What Frederick Douglass learned in Ireland.
3. How the early Standard Oil business model worked.
4. In praise of the Faroe Islands.
5. More Scott Sumner movie reviews. When I describe Scott as the best movie reviewer in the world today, what I mean is that if you follow his recommendations you get (should get?) higher consumer surplus than by following the recommendations of anyone else. An economist’s prize!
The Free Press is joining Paramount
Announcement here, congratulations!
And from the WSJ. And Katherine Boyle comments.
Sentences to ponder
To provide some sense of scale, that means the equivalent of about $1,800 per person in America will be invested this year on A.I.
Here is more from Natasha Sarin at the NYT.