Our paper on hospitals gaming Medicare payments AKA "turbocharging" (with Atul Gupta and @ambarlaforgia.bsky.social) is now in print! Ungated download here: sacarny.com/wp-content/u...

My (41M) 17 antagonistic agents have unionized

Cool #ASHEcon #ASHEcon2026 session alert: new work on hospital medical debt, private equity, and for-profit psychiatric hospitals! ft. @ambarlaforgia.bsky.social + me + others not on bluesky ⏰ Today! (Tuesday) 3:30-5pm 📍Hyatt Regency Greenway I 2nd Fl ashecon.confex.com/ashecon/2026...

Excited for tomorrow's #ASHEcon #ASHEcon2026 session chaired by Kosali Simon! @talgross.bsky.social will present new work our team is doing on nursing home payment and quality of care (discussant: Brian McGarry) ⏰ Monday 8:30-10am 📍Hyatt Regency Lakeshore B 1st Fl ashecon.confex.com/ashecon/2026...

Supposedly they are shutting down ResDAC in 5 weeks, and, I’m told, replacing them with a totally novice firm with no experience/expertise in Medicare data.

In a worker-firm effects (AKM) model, the worker+firm effects are only separately identified within mobility groups - the subgraphs of workers+firms connected by workers moving across firms. Something I just learned: the mobility groups for OLS vs. Poisson estimators are not necessarily the same.

I am blown away at how much faster Poisson regression runs in R with fixest/fepois than in Stata with ppmlhdfe. The speedup is on the order of 10x in our sample. We are doing bayesian bootstrap, i.e. we run the regression at least 300 times, so this is really helpful.

There are two Claudes

Our @jamahealthforum.com paper, "Prescription Drug Monitoring Program Reminder Emails, Program Use, and Prescribing" has been selected as a JAMA Network Clinical Trial of the Year! Read it here: jamanetwork.com/journals/jam...

I have learned that young researchers are running linear regression on large datasets and calling it “fwlmaxxing”

AI not liking my meeting style

Now available: my hospital cost report (HCRIS) code downloads and processes SNF cost reports, too. I've only tested it a little, so take with a grain of salt and let me know how it works for you! For now, it's a separate branch in the repository here: github.com/asacarny/hos...

Collaborator with AI-enabled Zoom was offline yesterday so I had to take notes by hand during the project call (this is also the plot of The Pitt season 2)

ChatGPT now insisting against all reason that Anderson, Indiana was a Metropolitan Statistical Area in 2020. So far it has linked to the 2020 OMB PDF, given me a page number, and provided a text extract showing it as an MSA. (Anderson, Indiana wasn't an MSA in 2020, all of this was hallucinated!!!)

CMS makes it official: no plans to cancel physical Medicare and Medicaid data access, forcing everyone to use the VRDC enclave. Instead, some more paperwork to make and extend DUAs – which is way better than what they were proposing!

It's that time of year again!! Attn all NYC-area health economists, submit your papers and mark your calendars for NYC Health Econ Day 2026 on Friday, May 1 at NYU Wagner. More info here: www.stern.nyu.edu/experience-s...

I'm on the #EconJobMarket! I study how policies and childhood environments shape outcomes of low-income & vulnerable kids. In my JMP, I study the effects of allowing youth who would have aged out of foster care at 18 to stay until 21—offering support their peers not in foster care get from parents.

Do you love health economics and learning about cool new research? Do you like telling other people about it? Come and be a social media editor at AJHE!! We're looking for someone to join our editorial team @ashecon.bsky.social

This is *extremely* bad (for the accuracy of my paper introductions about tech adoption)

@allanmjoseph.bsky.social has been telling me there needs to be a "Dartmouth Atlas, but for pediatrics" for maybe a literal decade? And now there is! (h/t to coauthor @johngraves.bsky.social)

Fun fact: you can estimate a conditional logit by running a fixed effects Poisson. They yield the same estimates and standard errors - they maximize the same likelihood. Poisson regression forever!

Very excited this is coming out soon! cc @ambarlaforgia.bsky.social

I thought I'd put the administration's proposed "compact" with universities in context, so I wrote the blog post below. It's especially for journalists covering this story! Many details about how the compact itself works and why the administration has retreated to this strategy.

The 2025 academic econ job market is trending better than the first COVID market year but worse than the rest of 2019-present www.davidvandijcke.com/joe_tracker/

The bus I've been taking this week makes local stops then runs on the highway. Like the bus in the movie Speed. It's all I can think about on my way in.

Out today in @jamapsychiatry.com: we find that inpatient psychiatric bed supply increasingly comes from freestanding psychiatric hospitals in large for-profit chains. Authors: Karen Shen @johnshopkinssph.bsky.social Mark Olfson @columbiapsych.bsky.social + me jamanetwork.com/journals/jam...

Yesterday I had the privilege of visiting the Broad Street pump! Sadly, I saw that the pump handle had been removed. I worked to reinstall the pump handle so local residents would not be deprived of this vital resource. So glad to bring some of the latest American public health ingenuity to London!

Statement from the largest economics association about the BLS firing As context: AEA approximately never makes such public statements This is a big deal

News reports say Columbia paid a "fine" of $200 million, which is grossly excessive, given the lack of any government authority to impose such a fine. On the blog, I parse the agreement and the stakes to explain what the dollar figure really reflects and its ominous implications. 👇

Characteristically clear-eyed thinking on the dangers of "regulation by deal" from my colleague David Pozen. balkin.blogspot.com/2025/07/regu...

Great rejoinder to a WSJ letter that (IMO quite incorrectly) interpreted the Oregon Health Insurance Experiment as showing that Medicaid doesn't improve health. www.statnews.com/2025/07/03/o...

Trying to identify opioids and other drugs in pharmacy data (claims, PDMP, etc.)? Use my code to quickly build a list of national drug codes (NDCs) using the free public database RxNorm. I wrote this code to replace the CDC's now-discontinued opioid NDC dataset. github.com/asacarny/dru...

My HCRIS hospital cost report code + data is updated through 2024! I threw the switch and moved everything to R. The new code lets you pull variables from the alphanumeric file, like hospital names and IDs. NB: I'm using this data now but pls think of it like beta testing. github.com/asacarny/hos...

A lot of you have been asking how my 10 million beneficial nematodes are doing. Well the answer is that me and my 10 million microscopic sons are doing great! Thanks so much

Currently in an ASHEcon session where my collaborator will be presenting our paper so I’m covering my name tag and whispering to people in the audience that I heard the last paper is really good with a very solid identification strategy

I know a lot is happening right now, so I want to pass along some happier news: I just purchased 10 million beneficial nematodes.

Extremely bad news is right. And I worry the same forces are coming for federal health care data.

This is TOMORROW!

Arguing with the IRB about publishing research out of quality improvement work

We published our 6 calls to action for the CU board of trustees today: www.columbiaspectator.com/opinion/2025... “We are at a crossroads in history where we can either succumb to authoritarianism or stand up against it.”

Come work with Kosali Simon & me @nber.org! We're hiring a Research Scientist to support exciting new work on Alzheimer's disease and dementia in Medicare. If you have a quant PhD, experience with claims data, and knowledge of R, it could be a great match! More info: www.aeaweb.org/joe/listing....

CMS asked the public for advice on how to move Medicare/Medicaid data users to their VRDC enclave, ending on-site physical access to this data. In my reply attached here, I say the best way to promote high-quality care and protect the trust fund is to maintain and *improve* on-site data access.

Proud to participate in this today

Columbia community! Join us tomorrow to stand with our colleagues in defense of of our students, patients, research, science, and teaching. Press conference immediately after at 1:15PM outside the Columbia gates on Amsterdam. ✊✊🏽✊🏾✊🏿 Follow: @cuimcstandsup.bsky.social @aaup.bsky.social

Join us on Monday as we call on Columbia and the Board of Trustees to resist the Trump administration's assault on our students, research, teaching and patients! 📍Low Library Steps ⏰ 12:30pm Monday April 14

NYC Health Econ Day is coming May 9 @ NYU Wagner! We'll have 6 great papers + lots of time to chat. Folks in the greater NYC area are invited! RSVP: docs.google.com/forms/d/e/1F... More info: www.stern.nyu.edu/experience-s... Organizers: @ambond.bsky.social, Mike Dickstein, Jessica Van Parys + me

Reducing administrative burdens helps people access support. If the govt already knows the answer to the question, why make you fill it out? www.nber.org/papers/w30885

of all the things the administration is doing, i am a little mystified by this effort to completely destroy the science, technology and medical research sector in the united states

A little update on this. I've now heard that the due date for amending a DUA to remove the word "gender" is specific to the DUA expiration date and *not* universally April 23

Every single university president should be asked, in public, why they are not speaking out this way to support all the students currently detained without due process, and all those terrified that they will be next, on every campus in this country. Yes, including Columbia's acting president.