iiinova — where your digital self keeps evolving

Sean Pinkney @spinkney.bsky.social · 24/08/2026

I pronounce "_rng" functions in Stan as "range" because it's giving me back a range of possibilities

Sean Pinkney @spinkney.bsky.social · 20/08/2026

Stancon26 talk about a surprising discovery I had that Bayesian hierarchical models can be made equivalent in distribution to frequentist estimates, giving new insight into hierarchical models and faster inference. Upcoming paper with Nikolai Vetr youtu.be/lHXav9KIEIU?...

youtu.be

Sean Pinkney - Population Effects in Hierarchical Models using Sum-to-Zero Constraints. StanCon 2026

YouTube video by Stan

0235

Sean Pinkney @spinkney.bsky.social · 09/08/2026

My favorite show as a child (I guess that dates me)

110

Sean Pinkney @spinkney.bsky.social · 09/08/2026

I spent the last 4 years thinking about this problem. I don't have time to write a paper so here's a blog post spinkney.github.io/posts/post-1...

spinkney.github.io

Bounded Correlation Matrices: Sign Constraints, Finite Boxes, and Exact Values – Pinkney’s Sufficient Stats

061

Sean Pinkney @spinkney.bsky.social · 03/08/2026

In world of llms, it's refreshing to see software designed with opinionated and pointed reasons

120

Sean Pinkney @spinkney.bsky.social · 28/07/2026

I bought Emily Wilson's translation of the Odyssey when it was released in 2017, posers

030

Sean Pinkney @spinkney.bsky.social · 21/07/2026

After a couple of months hiatus, a new blog post on directly parameterizing structural zeros in correlation matrices. spinkney.github.io/posts/post-1...

spinkney.github.io

Structural Zeros in Correlation Matrices: A Twelve-Parameterization Bake-Off – Pinkney’s Sufficient Stats

2186

Sean Pinkney @spinkney.bsky.social · 10/03/2026

Thank you R for eradicating measles from your ecosystem

0110

Sean Pinkney @spinkney.bsky.social · 15/02/2026

Hey, Alexa I do not want the hat below but I will buy one that says IGNORANCE IS STRENGTH WAR IS PEACE FREEDOM IS SLAVERY

010

Sean Pinkney @spinkney.bsky.social · 04/06/2025

Stan 2.37 will be out sometime next week. I helped get the updated simplex parameterization and sum-to-zero matrix (both rows and columns sum to zero). We found the new simplex parameterization to be much better in the extremes of the simplex and across very small alpha values of the dirichlet 1/

170

Sean Pinkney @spinkney.bsky.social · 02/06/2025

Ask me any questions you may have about this! #stats

0286

Sean Pinkney @spinkney.bsky.social · 07/05/2025

I've come on here after months away to let everyone know that I apparently really like trance music

000

Sean Pinkney @spinkney.bsky.social · 27/03/2025

Are there any other statistics nerds in the NoVA area that want to get together?

120

Sean Pinkney @spinkney.bsky.social · 17/02/2025

I don't know wtf this is but I'm super into matrices so the non-matrix theology is a non-starter for me

010

Sean Pinkney @spinkney.bsky.social · 03/02/2025

I will only be impressed by you if you solve a long standing mathematical conjecture and win the Tour de France within 2 years of each other. Otherwise, what are you even doing?

000

Sean Pinkney @spinkney.bsky.social · 31/01/2025

Basically he Colin from What We Do in The Shadows

100

Sean Pinkney @spinkney.bsky.social · 02/01/2025

"Painting to be stepped on." Do not step on the painting!

000

Sean Pinkney @spinkney.bsky.social · 02/01/2025

Tried zyn and that shit was so dysphoric. I don't smoke or take nicotine so probably too much. I had 1 slim pouch (2/4 strength) for 5 mins and then 10 mins later another pouch for 15 min. Initially I felt lightheaded, then I started sweating, felt nauseous, and couldn't wait for the effect to end

120

Sean Pinkney @spinkney.bsky.social · 26/12/2024

I have a 2017 MacBook pro and work supplied me with a m1max 32 GB about 3 years ago. I'm thinking I'll buy two or three mac minis and use them as a cluster. My son wants to start a twitch/yt stream and I think I can set up game screen capture better this way too. Any thoughts?

010

Sean Pinkney @spinkney.bsky.social · 02/12/2024

I'm going to have time to do 1-2 contributions for the summer 25 release. Here's my list to choose from, what is most interesting to you? - adding lower/upper bounds to ordered vectors (removing positive ordered since it's achieved by lb=0)

2143

Sean Pinkney @spinkney.bsky.social · 02/12/2024

A new release of Stan is coming discourse.mc-stan.org/t/cmdstan-st.... Highlights: New constraints for stochastic matrices and zero-sum vectors Easier user-defined constraints Improved diagnostics New distribution, beta_negative_binomial

discourse.mc-stan.org

CmdStan & Stan 2.36 release candidate

I am happy to announce that the latest release candidates of CmdStan and Stan are now available on Github! This release cycle brings new constrained types, improved diagnostics, and a new distributio...

083

Reposted by Sean Pinkney

James Balamuta @coatless.bsky.social · 29/10/2024

Woah, the new #Stan Playground lets you run MCMC in your browser & analyze the chains using #WASM powered #Rstats & #Python! 🎉 ✨ No installation needed - just write, compile, sample & analyze 🎯 Perfect for teaching & collaboration (share links ftw!) 🔗 Try it: stan-playground.flatironinstitute.org

stan-playground.flatironinstitute.org

Stan Playground

19534

Sean Pinkney @spinkney.bsky.social · 29/11/2024

First citation for my flexible parameterization of Cholesky factors of correlation matrices (arxiv.org/abs/2405.07286) this is in "Asymptotics for parametric martingale posteriors" by Edwin Fong, Andrew Yiu paper link at arxiv.org/abs/2410.17692.

030

Reposted by Sean Pinkney

Chad Scherrer @cscherrer.bsky.social · 19/11/2024

I got a Probabilistic Programming starter pack going. Hit me up if you're involved with #probprog R&D and want in! go.bsky.app/JfvubEf

2211630

Reposted by Sean Pinkney

Josiah Mortimer @josiahmortimer.bsky.social · 15/11/2024

NEW: "Moving Off X: An Open Letter from UK Journalists" UK political journalists: "Twitter was, for a long time, the place to be for UK politics. We believe that time is now over... "We have taken the decision to move over to other platforms, in particular Bluesky" docs.google.com/document/d/1...

We have used Twitter – now X – for many years. It has been a resource for story-gathering, network-building, and a megaphone for getting public-interest stories to a wider audience. And it has been a well of ideas and discourse.
Unfortunately that well is now poisoned.
All of us have seen X become more toxic and broken since Elon Musk took over in 2022.
Feeds have become less useful. Engagement has plummeted, except for those who will pay. Replies gain traction not through merit, but through the corrupted blue-tick system.
We have seen hate speech and abuse deliberately dialled up and amplified, boosted not just by the algorithm, but by the owner himself.
And England’s racist summer riots were one of many factors suggesting to us that X is not a neutral platform, but a space that now seems to glorify misinformation at a great cost to our public sphere.
Millions of people are ditching X, and we are doing so, too. We have taken the view that it is no longer a useful tool for objective reporting, but a weapon being wielded by a narrowing ideological set.
A tipping point is coming. Perhaps we are already in it.
After much consideration, we have taken the decision to move over to other platforms, in particular Bluesky. For some of us that means instantly deleting our X accounts, for others it is a more gradual process.
But we are all putting the majority of our efforts into building more constructive online spaces elsewhere for political dialogue and reporting.
Bluesky is becoming a new hub for political discussion, and we encourage other UK journalists to join and become active. We are already seeing far higher engagement on our posts there than we’ve seen recently on X.
And importantly, the mechanisms to limit abuse actually work.
We enjoyed Twitter while it lasted. It played an important role in shaping many of our careers. And it was, for a long time, the place to be for UK politics. We believe that time is now over.
Twitter is dead. Long live Twitter

12061531757

Reposted by Sean Pinkney

Jeremy Allen @jeremy-data.bsky.social · 26/10/2024

My fav starter packs so far, a thread: stats: go.bsky.app/Ki7PjpS stats: go.bsky.app/7TBN5rX causal inference: go.bsky.app/FdemGAZ package devs: go.bsky.app/N1569Qh data peeps: go.bsky.app/8TdEfdK medical stats: go.bsky.app/ArqEz36 bioinformatics: go.bsky.app/Ha64Gmv r-ladies: go.bsky.app/Vgxwa2F

18277132

Sean Pinkney @spinkney.bsky.social · 22/10/2024

This hierarchical model is getting ridiculous. Soft truncated multivariate normal priors with linear constraints, truncated MVN prior for > 0 constraint, all with a hierarchical hurdle model with the Dagum distribution

130

Sean Pinkney @spinkney.bsky.social · 23/09/2024

Wow, wow! I have a nice prior that helps to repel and attract gaussian mixture models for identification in bayesian modeling. Try the following simulation with 4 or more chains and see how crappy it is (even if you set mu to an ordered vector)

110

Sean Pinkney @spinkney.bsky.social · 23/09/2024

I have some cool attractive/repulsive methods for gaussian mixture models I'm playing with. Right now one method works well when the means overlap but not well when they don't. Anyway, should I write this up in a paper or just say fuck it and post it on the forums?

220

Sean Pinkney @spinkney.bsky.social · 21/09/2024

Is there a way to bookmark posts like on that other site?

010

Sean Pinkney @spinkney.bsky.social · 20/09/2024

Time for me to just get a blood boy

000

Reposted by Sean Pinkney

Aki Vehtari @avehtari.bsky.social · 20/09/2024

I'm looking for a post-doc and doctoral student to join my group at Aalto to work on Bayesian workflow, cross-validation, model checking, projection predictive model selection, inference diagnostics, priors, and survival analysis (I have plenty of research ideas, pick any combination) #Bayesian

099

Sean Pinkney @spinkney.bsky.social · 20/09/2024

Most of the internet Me: Hi internet stranger, can you do a simple thing that you've done before for me? Internet stranger: [silence] On the Stan forums Internet stranger: Can you derive this complicated thing that will help only me and my model? Me: [8 hours later] Here ya go.

2122

Sean Pinkney @spinkney.bsky.social · 19/09/2024

When you troll frequentists on LinkedIn

130

Reposted by Sean Pinkney

Matthew Kay @mjskay.com · 18/09/2024

Check out @stephenjwild.bsky.social's Bayesian starter pack go.bsky.app/UfgChHe

21811

Reposted by Sean Pinkney

Aaron Sojourner @aaronsojourner.org · 10/09/2024

For Bluesky-Curious Econ Lovers, a Quick Start guide to plugging into the economics community here. I wrote it hoping to lower the costs & boost the benefits for folks to engage here. If you think it's useful, please share it. 📉📈 #️⃣#️⃣ aaronsojourner.org/for-bluesky-...

aaronsojourner.org

For Bluesky-Curious Econ Lovers - Aaron Sojourner

This Quick Start guide aims to help econ lovers easily join Bluesky’s growing economics community. The Bluesky User FAQ covers generic basics, like how to start an account. This guide orients you to e...

815592