About me
I am a Postdoctoral Researcher at the Interdisciplinary Hub for Security, Privacy and Data
Governance (iHub) at Radboud University Nijmegen.
Here is a short overview of my CV
You can find my complete CV
here.
Research Interests
My research interests concern the interplay of
 Category Theory
 Probability Theory
 Programming Language Semantics
These fields come together in exciting ways in
categorical probability theory and
probabilistic programming. Some of the mathematical tools I use are
Markov categories and
quasiBorel spaces.
Other
areas I'm interested in: (Bayesian) machine learning, convex analysis, functional programming with effects, type theory, quantum computation, logic, topology and algebraic geometry.
Publications
You can find my DPhil Thesis here:
Structural Foundations for Probabilistic Programming Languages

Absolute continuity, supports and idempotent splitting in categorical probability
Tobias Fritz, Tomáš Gonda, Antonio Lorenzin, Paolo Perrone, Dario Stein (preprint)

Overdrawing Urns with Signed Probabilities
Bart Jacobs, Dario Stein, ACT 2023

Pearl's and Jeffrey's Update as Modes of Learning in Probabilistic Programming
Bart Jacobs, Dario Stein, MFPS 2023

A Category for unifying Gaussian Probability and Nondeterminism
Dario Stein, Richard Samuelson, CALCO 2023

Dilations and information flow axioms in categorical probability
Tobias Fritz, Tomáš Gonda, Nicholas Gauguin HoughtonLarsen, Paolo Perrone, Dario Stein (preprint)

Counting and Matching
Bart Jacobs, Dario Stein, CSL 2023

Probabilistic Programming with Exact Conditions
Dario Stein, Sam Staton. Invited Article, Journal of the ACM

Compositional Semantics for Probabilistic Programs with Exact
Conditioning
Dario Stein, Sam Staton. LICS 2021 Distinguished Paper

Probabilistic Programming Semantics for Name
Generation
Marcin Sabok, Sam Staton, Dario Stein, Michael Wolman. POPL 2021

The
BetaBernoulli process and Algebraic Effects
Sam Staton, Dario Stein, Hongseok Yang, Nathanael L. Ackerman, Cameron E. Freer, Daniel M. Roy.
ICALP 2018
Teaching
 Winter 202324, MFoCS Seminar at Radboud University Nijmegen
 Spring 23, Lecturer for Category Theory and Coalgebra, Radboud University Nijmegen
 Winter 202223, MFoCS Seminar at Radboud University Nijmegen
 Spring 2022, Tutor for Category Theory and Coalgebra at Radboud University Nijmegen
 Michaelmas 2020, Tutor for Categories, Proofs and Processes at University of Oxford
 Hilary 2020, Tutor for Quantum Information at University of Oxford
 Michaelmas 2019, Tutor for Principles of Programming Languages at University of Oxford.
 Hilary 2019, Tutor for Probability and Computing at University of Oxford.
Prospective Students: I am happy to cosupervise Bachelors Projects, Master's Projects and Research Internships. If you are interested in a topic, drop me an email! Below are some project ideas

A Groupoid of Shapes (BSc) Two fundamental operations on a matrix (for example in NumPy) are reshaping and transposition,
but iterating these operations can result in very complicated permutations. This problem can be approached elegantly using the notion of groupoid from category theory.
Goal: Develop a graphical language to understand such permutations, and answer some grouptheoretic questions about them
Tools: You will need an understanding of abstract algebra, groups and particularly permutation groups. No category theory is assumed. You will make experiments using the computer algebra system GAP.

Nominal Sets and Probability There are many formal relationships between fresh name generation (choosing a fresh variable name, or allocating a memory location) and probability.
Goal: There are different directions to explore, such as measures on nominal sets, combining probability and name generation, and studying the structure of name generation as a Markov category

A Type Theory for Equivariance Group actions are a fundamental idea to understand mathematical structures with symmetries.
Goal: Develop a polymorphic type theory for group actions, where everything that typechecks is equivariant by construction
Talks
 Nov 2023, DutchCATS 2023, Radboud Universiteit Nijmegen
 Jul 2023, ACT 2023, University of Maryland
 Jun 2023, MFPS 2023, Bloomington, Indiana
 Jun 2023, CALCO 2023, Bloomington, Indiana
 May 2023, Southern Logic Seminar, UCL
 Feb 2023, CSL 2023, University of Warsaw
 Jan 2023, Inn'formal Probability Seminar, Universität Innsbruck
 Aug 2022, Introduction to Probabilistic Programming, SWS Seminar, Radboud University Nijmegen
 Jul 2022, "A Hypergraph Category for Exact Gaussian Inference", Applied Category Theory 22 (slides, video), Strathclyde
 Jul 2022, Tutorial on Probabilistic Programming, iHub, Radboud University Nijmegen
 Jul 2021, Mathematical
Foundations Seminar, Bath
 Jul 2021, VeriProP 2021
 Jun 2021, LICS 2021
 Jan 2021, Oxford Quantum Group Workshop
 Jan 2021, POPL 2021
(View on
Clowdr)
 Jan 2021, LAFI. Slides
 Oct 2020, ProbProg workshop, MIT/Online
 Feb 2020, PIHOC workshop, IRIF, Paris. Slides
 Jan 2020, LAFI workshop, POPL, New Orleans. Slides
 2019, Junior Semantics Seminar x 2, Oxford
 Jul 2018, ICALP 2018, Prague.
 2018, Quantum Lunch, Quantum Group, Oxford
Service
 PC for ProbProg'21, LAFI'23
 Reviewer for Compositionality, MSCS, FSCD, ProbProg'21 PC, LICS'22, MFCS 2022, FoSSaCS 2023, ESOP 2023, FoSSaCS 2024