François-Xavier Briol
@fxbriol.bsky.social
4.1K followers 450 following 30 posts
Professor of Statistics and Machine Learning at UCL Statistical Science. Interested in computational statistics, machine learning and applications in the sciences & engineering.
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fxbriol.bsky.social
Thanks Robin! And of course your very nice review of ABC was very helpful (and can be found in the references for those interested!).
fxbriol.bsky.social
Thanks for the interest! I'll send you a separate copy without the breaks via email, but I don't think it'll be better because I tend to make various parts of the slide appear/disappear, so removing breaks will make things look very messy.
fxbriol.bsky.social
Just finished delivering a course on 'Robust and scalable simulation-based inference (SBI)' at Greek Stochastics. This covered an introduction to SBI, open challenges, and some recent contributions from my own group.

The slides are now available here: fxbriol.github.io/pdfs/slides-....
Reposted by François-Xavier Briol
pierrealquier.bsky.social
I'll give a talk at the BayesComp workshop on 'Bayesian Computation and Inference with Misspecified Models' Tuesday. Come and say "hi!" if you are attending BayesComp!

Workshop website and schedule:
postbayes.github.io/BayesMisspec...
Reposted by François-Xavier Briol
Composite Goodness-of-fit Tests with Kernels, now out in JMLR!

www.jmlr.org/papers/v26/2...

Test if your distribution comes from ✨any✨ member of a parametric family. Comes in MMD and KSD flavours, and with code.

@oscarkey.bsky.social @fxbriol.bsky.social Tamara Fernandez
Composite Goodness-of-fit Tests with Kernels
www.jmlr.org
Reposted by François-Xavier Briol
ec.europa.eu
Choose Science. Choose Europe.

A new Marie Skłodowska-Curie Actions Postdoctoral Fellowships 2025 call is now open.

With a budget of €404.3 million, it will support around 1,650 researchers from Europe and beyond.

Apply by 10 September → europa.eu/!fBTMgF
A graphic for the Marie Skłodowska-Curie Actions (MSCA), showing a historical portrait of Marie Skłodowska-Curie overlaid with an image of four young researchers walking down a hallway. The European Commission logo is in the top left. Text reads: "Marie Skłodowska-Curie Actions – €404.3 million to support postdoctoral researchers”
fxbriol.bsky.social
Well done again to @hudsonchen.bsky.social on his very first ICML paper! 😎
fxbriol.bsky.social
Surprisingly, @hudsonchen.bsky.social was able to prove a very fast convergence rate! He showed an interpolation rate whereas it was previously believed that only a much slower noisy regression rate was feasible! 🤯

This improves on our prior work: arxiv.org/abs/2406.16530 and all competing methods.
Conditional Bayesian Quadrature
We propose a novel approach for estimating conditional or parametric expectations in the setting where obtaining samples or evaluating integrands is costly. Through the framework of probabilistic nume...
arxiv.org
fxbriol.bsky.social
Our paper remedies the problem with a very simple algorithm which is a nesting of two kernel quadrature algorithms. This provably reduces the number of samples needed to obtain a given accuracy when the problem isn't too high dimensional and smooth.
fxbriol.bsky.social
Unfortunately, existing methods such as nested Monte Carlo or multilevel Monte Carlo require a huge number of samples at each level of nesting to estimate these accurately! ☹️
fxbriol.bsky.social
Why should you care? Nested expectations are a significant computational challenge in stats/ML: they arise in active learning, Bayesian optimisation, experimental design, but also other fields such as option pricing and health economics.
fxbriol.bsky.social
New ICML 2025 paper: Nested expectations with kernel quadrature.

We propose an algorithm to estimate nested expectations which provides orders of magnitude improvements in low-to-mid dimensional smooth nested expectations using kernel ridge regression/kernel quadrature.

arxiv.org/abs/2502.18284
fxbriol.bsky.social
Huge congrats to William Laplante (williamlaplante.github.io) on his first paper, completed in the first few months of his PhD!

And thanks to all collaborators including
@maltamiranomontero.bsky.social, Andrew Duncan and Jeremias Knoblauch.
William Laplante
williamlaplante.github.io
fxbriol.bsky.social
The paper builds on the robust and scalable Gaussian process (RCGP) algorithm from our ICML 2024 paper (arxiv.org/abs/2311.00463). It shows that it can make use of common computational tricks in spatio-temporal settings, and also uses adaptive hyper parameter optimisation to improve calibration.
Robust and Conjugate Gaussian Process Regression
To enable closed form conditioning, a common assumption in Gaussian process (GP) regression is independent and identically distributed Gaussian observation noise. This strong and simplistic assumption...
arxiv.org
fxbriol.bsky.social
New ICML 2025 paper: Robust Spatio-Temporal GP Regression!

We propose a new GP method with linear-in-time cost that is provably robust to outliers. Unlike competitors, our method is fully conjugate and requires no expensive variational inference!

📄 arxiv.org/abs/2502.02450
fxbriol.bsky.social
If you are at AISTATS this week, check out our paper on cost-aware simulation-based inference!
fxbriol.bsky.social
Thanks Pierre! I think it could be quite handy for MMD-Bayes and MMD estimators :).
fxbriol.bsky.social
Ever used kernel mean embeddings or MMD? Wished you had a closed-form expression so you wouldn't need to estimate these? See our new paper with Alex Gessner, Toni Karvonen and Maren Mahsereci, which comes with an associated Python package. arxiv.org/abs/2504.18830
A Dictionary of Closed-Form Kernel Mean Embeddings
Kernel mean embeddings -- integrals of a kernel with respect to a probability distribution -- are essential in Bayesian quadrature, but also widely used in other computational tools for numerical inte...
arxiv.org
Reposted by François-Xavier Briol
serge.belongie.com
So far, 2,135 people have responded to the poll Søren and I posted a few days ago. Of those, 94.4% replied “Yes” to being interested in officially presenting accepted @neuripsconf.bsky.social papers in Europe. (1/7)
fxbriol.bsky.social
We also have excellent line-up of invited speakers which includes @pierrealquier.bsky.social, @eweinstein.bsky.social, Jeremias Knoblauch, David Frazier, Harita Dellaporta, Antonietta Mira, Jeremie Houssineau, Sonia Petrone, Edwin Fong and Aretha Teckentrup.
fxbriol.bsky.social
The BayesComp workshop on 'Bayesian Computation and Inference with Misspecified Models' will take place in Singapore on the 16-17th June.

We have an open call for posters/contributed calls, with a deadline on the 1st May. More details on the website:
postbayes.github.io/BayesMisspec...
BayesComp Satellite Workshop on Bayesian Computation and Inference with Misspecified Models
postbayes.github.io