Brendan J. Kelly

StanCon 20206 International Conferene on Bayesian Inference and Probabilistic Programming 17-21 August, 2026 Uppsala, Sweden

Three weeks time to submit contributed talk abstract to StanCon 2026! You can also submit a poster abstract early, if you need to make early travel plans. There will be travel and accommodation support for students, too!

More information about submitting at www.stancon2026.org/abstracts/

The Crime of Witness | Fintan O’Toole Renée Good and Alex Pretti were murdered for daring to interfere with the Trump administration’s efforts to normalize abductions and state violence.

Fintan O’Toole @fotoole.bsky.social on the murders of Renée Good and Alex Pretti https://go.nybooks.com/4bmNB4F

YouTube video by Molarkie Alfred Hitchcock's 1942 Saboteur (Scene)

Watched #Saboteur last night -- #Hitchcock captured the internal battle between democracy and fascism in 1942. A reminder that American fascists were fighting against democracy even during WW2: youtu.be/-rtlkILRmEQ

from what I can see, the video shows a beating followed by an execution.

StanCon 2026 Deadline for tutorial and workshop in one week Hi everyone, The submission deadline for contributing tutorials and workshops is one week from now, on the 28th of January. Tutorial Tutorials provide hands-on learning experiences to help attendee...

StanCon 2026 tutorial and workshop deadlines in one week:
discourse.mc-stan.org/t/stancon-20...
@mc-stan.org

When works become public domain, anyone can reimagine and reuse them.

🚂 The Little Engine That Could can be freely reinterpreted—like this video marrying pages of the 1930 book to a Librivox audio recording. 📚+🎤

Learn more ⤵️
blog.archive.org/2026/01/01/w...

#PublicDomainDay

And we're live, Lecture A1 is online. Introduction to Bayesian workflow, generative models, estimands, estimators, estimates, error checking, beginnings of probability theory and Bayesian updating. www.youtube.com/watch?v=ztbY...

State-of-the-Art Review: Infectious Diarrhea This State of the Art Review describes a multidisciplinary approach to the care of people with diarrhea, considering both infectious and non-infectious eti

Great overview of current knowledge.

Many patient factors impact the management of people w/ presumed infectious diarrhea. Therefore, multispecialty engagement optimizes access, linkage to care, and judicious use of diagnostics and therapeutics…

academic.oup.com/cid/article/... #IDSky

Incremental development and testing: Black cat adoptions Even when we know the final statistical model that we want to use for inference, we should not try to write it directly. It is better to develop simpler, incremental models and test each with synthetic data. This helps us to avoid the frustration of trying to debug a complex model. Large models can and usually do fail in multiple ways, due to a poison salad\subjindex{poison salad} of coding errors, misspecification, and estimation challenges. % Being smart means working smart. By starting with a simple, minimal model and adding one feature at a time, we have a better chance of knowing which portion of the model code is responsible for an error, misspecification, or poor convergence. This case study builds the target statistical model in several steps, while using synthetic data simulation to help construct and test each incremental model. This helps us construct the model, notice and evaluate alternative implementations, and better understand how the model performs. This case study also provides an example of survival analysis with censoring. This kind of problem is commonplace---there are observations that are only partially observed, and we need to use all the information, even if only partial. Bayesian implementation provides two different ways to implement censored observations, by using cumulative distributions corresponding to the ordinary data model or by treating each censored value as partially observed and imputing it using the data model. Neither approach is always superior, and each helps us understand the model better. We'll show you both. Another benefit of this kind of example is the generative model of the sample and the statistical model necessarily differ. We often say Bayesian models are generative, they can be used to simulate observations. And that's true. But it isn't always true of every aspect of the model. In the case of censored values, the censoring is part of the observation m…

Prior predictive distribution of waiting times for the first adoption model (without censoring). Each curve is a survival plot for an individual prior simulation. Black curves correspond to black cats. Orange curves correspond to all other cat colors.

Posterior predictive distributions of waiting times for the first adoption model (without censoring). Each curve is a survival plot for an individual posterior simulation. Black curves correspond to black cats. Orange curves correspond to all other cat colors.

Including the old black cat adoptions survival analysis example as a case study in the forthcoming Bayesian Workflow book. This is presented as a whole incremental workflow with simulation, validation, and model comparison. Just now went through code and extra-commented and cleaned. Getting close!

We're doing the final sprint, and I think we're able to send the PDF of the forthcoming Bayesian Workflow book to the publisher in the next two weeks (500+ pages), which would mean it would be published some time next year

American food safety could be headed for a breakdown More Americans will be exposed to foodborne illness as a result of this year's funding cuts, food safety experts predict

American food safety could be headed for a breakdown. Story by @sarah-todd.bsky.social www.statnews.com/2025/12/22/a...

Grading and googling hallucinated citations, as one does nowadays, and now that LLMs have been around for a while, I've discovered new horrors: hallucinated journals are now appearing in Google Scholar with dozens of citations bc so many people are citing these fake things

course schedule as a table. Available at the link in the post.

I'm teaching Statistical Rethinking again starting Jan 2026. This time with live lectures, divided into Beginner and Experienced sections. Will be a lot more work for me, but I hope much better for students.

I will record lectures & all will be found at this link: github.com/rmcelreath/s...

Perspective "The net effect would be to disadvantage the people the FDA exists to protect, including millions of Americans at high risk from serious infections." "A Threat to Evidence-Based Vaccine Policy and Public Health Security at the FDA" by R.M. Califf et al.

Twelve former commissioners of the FDA express concern that the agency’s recent moves will undermine a regulatory model designed to ensure vaccine safety, effectiveness, and availability. Read the full Perspective: nej.md/48Ova76

Modelling Like an Experimentalist Dahlin et al. (2024) apply experimental thinking to a model of mosquito-borne disease transmissions.

"Validate With Simulated Truth: A first habit is to test whether an analytical pipeline can recover known conditions."

Very good advice below. So much COVID nonsense (e.g. 'immunological dark matter') basically came down to a non-identifiable model that hadn't been properly tested.

Pseudomonas aeruginosa has big slug energy. #IDsky #MicroSky

Effectiveness of Nirmatrelvir/Ritonavir or Molnupiravir Use in Immunocompromised Patients on B-Cell–Depleting Therapy With COVID-19: A Target Trial Emulation Study This target trial emulation study assessed nirmatrelvir/ritonavir and molnupiravir effectiveness in COVID-19 patients receiving B-cell–depleting therapy. N

A study of COVID therapeutics in immunocompromised individuals on B-cell depleting therapy!!!

Nirmatrelvir/ritonavir significantly more effective than no rx (HR 0.56) molnupiravir w non significant trend to improved outcomes (HR also 0.56)… #IDSky #covid

academic.oup.com/cid/advance-...

On an Arctic archipelago, frozen soil may preserve a hidden history of viruses Scientists are hunting for ancient RNA in Svalbard’s permafrost, hoping to shed light on the evolution of viral diseases

I am fascinated by how viruses evolve - and not just since #SARSCoV2 has shown us at the global stage how consequential virus evolution can be for us.
In my new story in @science.org I got to explore how researchers are probing deeper into the past with old RNA virus genome.
So a 🧪 thread…

💻Join online! 🎧
Süßmilch Lecture at the Max Planck Institute for Demographic Research (MPIDR)
Putting Science Before #Statistics
🗣️Richard McElreath 🐈‍⬛ MPI-EVA Leipzig
📅Oct 21, 2025
🕒3 pm CEST
✏️Sign up now:
https://ow.ly/uxfc50Xb5Yx

Is a healthy microbiome one that is rich in phages? 🦠 Excited to share our paper out in Lancet Microbe with @bkoskella.bsky.social & @dholtappels.bsky.social where we test whether virome diversity can be used a broad signature of microbiome health 📈

What could possibly go wrong? #IDSky

ELLIS PhD Program: Call for Applications 2025 The ELLIS mission is to create a diverse European network that promotes research excellence and advances breakthroughs in AI, as well as a pan-European PhD program to educate the next generation of AI...

I'm looking for a doctoral student with Bayesian background to work on Bayesian workflow and cross-validation (see my publication list users.aalto.fi/~ave/publica... for my recent work) at Aalto University.

Apply through the ELLIS PhD program (dl October 31) ellis.eu/news/ellis-p...

Fantastic discussion of the BALANCE trial -- and randomized trial preparation / design in general. Also, great to hear Communicable and Breakpoints teaming up! #IDSky

"It turns out boredom is the Cadillac of feelings."

library(tidyverse) mtcars |> head(8) |> rownames_to_column("name") |> ggplot(aes(x = drat, y = name, fill = name)) + geom_col() + theme(panel.widths = unit(50, "mm"), panel.heights = unit(50, "mm"))

The new ggplot2 4.0.0 now supports absolute plot dimensions 🤩

#rstats #dataviz #phd

#IDsky

Happy International Microorganism Day! 🎉

Today, we are celebrating the tiny powerhouses that have a massive impact on our world. From the bacteria in our gut to the fungi that give us antibiotics, these incredible organisms are essential to life.

Let's make some noise for the microscopic!

Typhus, a disease once nearly eradicated in the U.S., is on the rise in Texas Texas is seeing an explosion of cases of typhus, a disease that – if untreated – can be fatal. Typhus was almost eradicated from the United States, but now it's making a comeback.

Typhus, a disease once nearly eradicated in the U.S., is on the rise in Texas

"76-year-old Clark contracted #typhus from clearing weeds from her garden"
🦠

flip.it/Zzrht7

Learning ecosystem-scale dynamics from microbiome data with MDSINE2 - Nature Microbiology This Bayesian statistical method uses timeseries microbiome data to infer interaction modules and is tested using a faecal transplant experiment in mice.

#Newresearch

This Bayesian statistical method uses timeseries microbiome data to infer interaction modules and is tested using a faecal transplant experiment in mice.

#MicroSky

www.nature.com/articles/s41...

David Rose memorial poster

Remembering David Rose today. www.bbc.com/news/article...