Many interventions “work” in small trials but fail at scale Also, EdTech often promises much, but delivers little In a new paper (bit.ly/3JKLgVn) @karthik-econ.bsky.social & I show how personalized adaptive learning (PAL) software can sharply improve learning outcomes at scale🧵1/16

“Over the past 20 years, Paris has undergone a major physical transformation, trading automotive arteries for bike lanes, adding green spaces and eliminating 50,000 parking spaces. Part of the payoff has been invisible — in the air itself.” Leadership, strategy, real action, common sense. #Paris

Some professional news: I'll be starting as a co-editor at the Journal of Development Economics. I'll do my best to be constructive, fair, and fast. Looking forward to reading what you are all up to... as I hope you are looking forward to my future referee requests #EconSky

🚨Excited to announce a free mini-course on Modern Difference-in-Differences Designs, taught by @borusyak.bsky.social , hosted by ITAM & LACEA's Impact Evaluation Network! 🚨 🗓️ Sept 26–27, 2025 📍 ITAM's Santa Teresa campus, CDMX Details 👇 #EconTwitter

Hey #econsky: Does your department offer some type of incentive (e.g. teaching relief) for serving in an editorial role (editor/co-editor) of a top journal (say top field or higher)?

New paper by @njudd.com shows that an additional year of education doesn't causally affect telomere length in old age, despite many (theory) accounts arguing otherwise. It's been desk rejected by 13 journals happy to publish small 'positive' telomere studies. Sigh. www.biorxiv.org/content/10.1...

📚 At the #JRF annual meeting, our Research Fellows engaged in three days of structured exchange, sharing research, building interdisciplinary connections, and advancing ideas to improve learning outcomes for children worldwide. Meet the fellows 👥 bit.ly/4kQMPij #Education #Research #Fellows

Nice to be back with @jacobsfoundation.bsky.social among fellow fellows! @alexeble.bsky.social @marome1.bsky.social @boldinsights.bsky.social ➡️ For those interested in the future: jacobsfoundation.org/activity/jac... @blavatnikschool.bsky.social @wwhglobaled.bsky.social @oxfordcsae.bsky.social

The tragic landslide in Blatten gives me the excuse to tell you the story of how we found out Ice Ages existed. It's a cool story and the most important bit is rather similar to what's happening now.

In the most recent issue of @restatjournal.bsky.social (direct.mit.edu/rest/article...), we (Kaspar Wuthrich and @karthik-econ.bsky.social) provide guidance on how to analyze and design experiments with factorial designs (or cross-cuts). A 🧵 below:

Finally in print @restatjournal.bsky.social 😀!

Portrait of dad, by my 3 years old

Thanks to everybody who chimed in! I arrived at the conclusion that (1) there's a lot of interesting stuff about interactions and (2) the figure I was looking for does not exist. So, I made it myself! Here's a simple illustration of how to control for confounding in interactions:>

On the verge of declaring defeat with chatgpt in my asynchronous online dataviz class. Something changed this semester compared to past ones and SO MANY assignments are essentially 100% LLM output.

"...esa condescendencia maquillada de amabilidad, una entrada más de ese diccionario no verbal que organiza los códigos entre ciertos burgueses" de Cien Cuyes de Gustavo Rodríguez

Cat: "Ahhh yes perfect, my evil plan is working...if I cuddle here he won't be able to work and will have to pet me"

I'll be presenting tomorrow at the joint Harvard-MIT Development seminar (2:30 p.m.- 4 p.m.). Friends working on econ or edu in Boston/Cambridge, come over to say hi if you've got nothing else on!

My 3-year-old said he dreamed of our cat riding a flying jaguar (like the one in Coco)… I should ask him to share whatever he's on.

Gran libro Salvar El Fuego de Guillermo Arraiga. Empieza así:"Este país se divide en dos: en los que tienen miedo y en los que tienen rabia. Ustedes, burgueses, son los que tienen miedo...Nosotros vivimos con rabia...Nacemos sin vida, sin futuro, sin nada. Pero somos libres porque no tenemos miedo."

Interesting new paper: arxiv.org/pdf/2503.09907 improves on both rdrobust and rdhonest! Quite compelling... 1/n

"The world must now affirm that human lives matter, no matter where they are." -- Abhijit Banerjee and Esther Duflo in today's FT.

Llueve en la sabana

It never ceases to amaze me how I still go back to MHE, even when discussing how to implement fancy modern causal forest methods, to check how to do things properly

This effort was only possible because these journals require data and code repositories. This allowed us to compare data across papers and identify undisclosed connections between 15 studies (e.g., overlapping samples, overlapping interventions, reused treatment assignment).

After being alerted about possible misconduct, the I4R are reproducing published papers that use data from a specific NGO (GDRI). This thread releases the first 2 reports and provides more information about the work and responses/statements from authors journals and journals. 🧵

Dear co-authors, please list 5 things you did on our paper last week.

Replacing "I hope this email finds you well" with "Failure to respond will be taken as a resignation." in all emails from now on.

@yann-lecun.bsky.social on what the EU needs to attract top scientists from the US. AFAIK only Swiss unis plus very few others solve all 7 criteria. Eg Sweden IMO solves the rest (=some great clusters!), but not #3. That retains some intra-EU talent but it's hard to hire from R1 US unis

Just published in @jpube.bsky.social: "The environmental cost of power outages: Evidence from Delhi" By Yatang Lin & Dana Kassem

Elon says 90% of US aid never reaches communities. He confuses USAID's 90% reliance on intermediaries -- US companies delivering HIV drugs, WFP delivering food aid -- with waste. Comical if not so dangerous. @rachelbonnifield.bsky.social & I break down where aid goes: www.cgdev.org/blog/no-90-p...

USAID.gov has gone dark. USAID continues until Congress says otherwise, or our constitutional order crumbles, whichever comes first.

The Internet Archive has to date downloaded 500 terabytes of US government websites, which it crawls at the end of every presidential term. The whole archive is fully searchable. This effort's housed by a donation-funded nonprofit, not a branch of the US government. blog.archive.org/2024/05/08/e...

The Demographic and Health Surveys, a major effort supported by USAID and widely used across the world, are also not currently available.

Here's my generic ebike buying guide: Get one with a motor from one of these companies (Bosch, Brose, Shimano, SRAM, Panasonic, Yamaha, Giant, or Specialized), front and back thru-axle (not quick release) for the wheels, and hydraulic (not mechanical) disc brakes. They will have decent batteries.

The Mexico City Policy cuts off U.S. aid to health groups in other countries that offer abortion services or counseling. As in 2021, Trump has reinstated this policy, which was deactivated by Biden.

Postales Uniandinas. El gran @jccarden.bsky.social dando clase en la plazoleta del Lleras.

Today is an R&R day—the academic version of winning the lottery (with extra work attached). @singhabhi.bsky.social

"A ella no le gusta trabajar Lo que le gusta es bailar Moviendo las caderas siempre va Con su caguama" open.spotify.com/track/1bEUbY...

I ❤️ Bogotá

Today is AEA P&P submission deadline day ... ... or, as I like to call it, "economist resume padding day"! Economists with more P&Ps are more likely to list them in a way that is difficult to distinguish from refereed ones (i.e., real AER articles). papers.ssrn.com/sol3/papers....

Going to Bogotá in a couple of weeks. So nerdy me made a bunch of city maps 🤓 Fun fact about Latin American cities: the richest neighborhoods tend to be dense and full of apartment buildings.

The lesson from New York is that no amount of density and transit access will prevent a small but vocal segment of the population from being complete babies about congestion pricing. So just do it anyway! Your city will be better for it.

Here are the first five sets of slides: 01 Introduction: psantanna.com/DiD/01_Intro... 02 Classical 2x2 setup: psantanna.com/DiD/02_two_b... 03 Clustering issues: psantanna.com/DiD/03_Clust... 04 Functional form: psantanna.com/DiD/04_Funct... 05 Covariates: psantanna.com/DiD/05_Covar...

After years work assembling and organizing it, together with Bruno Calderón, John Marshall and José Luis Perez Castellanos, we present you the "Electoral precinct-level database for Mexican municipal elections" osf.io/6jteh/ dropbox.com/scl/fi/3kqnb...

La sabana de Bogotá

🚨New working paper! The pandemic raised housing prices in the suburbs relative to the centers of cities. But not in Mexico City! “Housing price gradients in Mexico City during the Covid-19 Pandemic“ With Diego Mayorga and Karla Neri tinyurl.com/28ruzuf3 #EconSky

En este hogar nos gusta mezclar ritmos