Stuart Burrell
Manager, AI Research
Visa
140 Science Park, Cambridge, UK
sburrell@visa.com
Bio
I'm a Manager of AI Research at Visa in the Risk and Identity Services division, where we build real-time AI/ML systems for combating financial crime - a rising epidemic with links to organised crime, human trafficking, and even terrorism.
Before moving to industry, I was a research fellow at the University of St Andrews in geometric measure theory, funded by an early career fellowship from the London Mathematical Society and the Heilbronn Institute for Mathematical Research.
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Visa 2025 - presentManager, AI Research
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Featurespace 2022 - 2025Lead Research Engineer
Senior Research Engineer
Research Scientist -
University of Cambridge 2021 - 2022MPhil in Machine Learning and Machine Intelligence
Advisor: Prof. M. van der Schaar -
University of St Andrews 2021Postdoctoral Researcher
London Mathematical Society Early Career Fellowship
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University of St Andrews 2016 - 2020PhD in Mathematics
Advisors: Prof. J. Fraser & Prof. K. Falconer
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University of St Andrews 2012 - 2016MMath in Mathematics
Advisor: Prof. L. Thomas
Publications
Local Normalization Distortion and the Thermodynamic Formalism of Decoding Strategies for Large Language Models
T. Kempton*, S. A. Burrell*
Preprint, 2025.
Fairness-Aware Low-Rank Adaptation Under Demographic Privacy Constraints
P. Kamalaruban, M. Anderson, S. A. Burrell, M. Madigan, P. Skalski, and D. Sutton
Submitted.
TempTest: Local Normalization Distortion and the Detection of Machine-Generated Text
T. Kempton*, S. A. Burrell*, and C. Cheverall
AISTATS, 2025.
Evaluating Fairness in Transaction Fraud Models: Fairness Metrics, Bias Audits, and Challenges
P. Parameswaran, Y. Pi, S. A. Burrell, E. Drage, P. Skalski, J. Wong and D. Sutton
International Conference for AI in Finance, 2024.
Locally Differentially Private Embedding Models in Distributed Fraud Prevention Systems
I. Perez, J. Wong, P. Skalski, S. A. Burrell, R. Mortier, D. McAuley and D. Sutton
ICDM Data Mining in Finance, 2023 (Oral presentation).
Towards a Foundation Purchasing Model: Pretrained Generative Autoregression on Transaction Sequences
P. Skalski, D. Sutton, S. A. Burrell, I. Perez and J. Wong
International Conference for AI in Finance, 2023 (Oral presentation).
The Fractal Structure of Elliptical Polynomial Spirals
S. A. Burrell, K. J. Falconer and J. M. Fraser
Monatsh. Math., Vol. 199, pp. 1–22, 2022.
Dimensions of Fractional Brownian Images
S. A. Burrell
Journal of Theoretical Probability, Vol. 35, pp. 2217-2238, 2022.
Projection Theorems for Intermediate Dimensions
S. A. Burrell, K. J. Falconer and J. M. Fraser
Journal of Fractal Geometry, Vol. 8, No. 2, pp. 95-116, 2021.
Digit Expansions of Numbers in Different Bases
S. A. Burrell, H. Yu
Journal of Number Theory, Vol. 226, pp. 284-306, 2021.
Coincidence and Disparity of Fractal Dimensions
S. A. Burrell
PhD Thesis, University of St Andrews, 2021
The Dimension of Inhomogeneous Self-affine Sets
S. A. Burrell, J. M. Fraser
Annal. Acad. Sci. Fenn. Math., Vol. 45, pp. 313-324, 2020.
On the Dimension and Measure of Inhomogeneous Attractors
S. A. Burrell
Real Analysis Exchange, Vol. 44, No. 1, pp. 199-216, 2019.
Talks
Innovations in AI for fighting financial crime
Centre for Doctoral Training in Data Intensive Science, University of Cambridge, January 2025
How to fight fraud with Generative AI
Keynote speaker at NVIDIA AI FSI Community meet-up, London, November 2024
Building a map of machine learning
Invited speaker at National Centre for Atmospheric Science Workshop, University of Leeds, February 2024
Careers in industrial R&D
Invited speaker at Carnegie PhD Scholars Gathering, Playfair Hall, Edinburgh, December 2023
Natural language interfaces
Centre for Doctoral Training in Data Intensive Science, University of Cambridge, November 2023
Sundials, dimensions and fractal projections
The Royal College of Physicians and Surgeons, Glasgow, February 2019
Positive problem solving
First Chances Scheme, University of St Andrews, February 2019
The journey to a PhD in Mathematics
UWS Summer STEM Academy, Glasgow, July 2018
Fractal geometry in nature and art
The Royal Society of Edinburgh, February 2018
The elliptical spiral mapping problem
Dynamic Days Europe, Nice, France, August 2021
Local structure of elliptical polynomial spirals
British Early Career Mathematicians’ Colloquium, July 2021
Dimension and deformation of elliptical polynomial spirals
Junior Ergodic Theory Meeting (JETS), November 2020
Projection theorems for intermediate dimensions
Thermodynamic Formalism: Ergodic Theory and Geometry, University of Warwick, United Kingdom, July 2019
Inhomogeneous attractors: an introduction and recent developments
Edinburgh Mathematical Society PG Student Meeting, The Burn, Glen Esk, May 2019
The dimensions of inhomogeneous self-affine sets
Fractals and Stochastics VI, KIT, Germany, October 2018
A brief note on the dimension of inhomogeneous attractors
Dynamics Days Europe, University of Loughborough, September 2018
A universal upper bound on the dimension of inhomogeneous attractors (speed talk)
British Mathematical Colloquium, University of St Andrews, June 2018
How big are inhomogeneous attractors?
Edinburgh Mathematical Society PG Student Meeting, The Burn, Glen Esk, May 2018
Inhomogeneous attractors and upper box dimension
Fractals and Dimensions, Institut Mittag-Leffler, Sweden, December 2017
Inhomogeneous attractors and upper box dimension
Fractals and Dimensions, Institut Mittag-Leffler, Sweden, December 2017
Introduction to trace contrast methods
Estimating Animal Density with Acoustics, University of Cape Town, South Africa, January 2017
Trace contrast methods in acoustic space
African Institute for Mathematical Sciences, South Africa, January 2017
Introduction to trace contrast methods
Estimating Animal Density with Acoustics, University of Cape Town, South Africa, January 2017
Trace contrast methods in acoustic space
African Institute for Mathematical Sciences, South Africa, January 2017
Brownian tumbleweed, dimension and the spiral mapping problem
Pure Analysis Seminar, University of St Andrews, November 2020
Interdimensional travel
Pure Postgraduate Seminar, University of St Andrews, February 2020
Projections, capacities and intermediate dimensions
Pure Analysis Seminar, University of St Andrews, November 2019
Energetic dimension interpolation on projections of sets
Pure Analysis Seminar, University of St Andrews, March 2019
Capacity theoretic approaches to dimension
Pure Postgraduate Seminar, University of St Andrews, March 2019
Foundations and applications of fractal geometry
Postgraduate Interdisciplinary Mathematics Symposium, The Burn, Glen Esk, January 2019
Dimension drop and inhomogeneous self-affine sets
Pure Analysis Seminar, University of St Andrews, October 2018
On the dimension and measure of inhomogeneous attractors
Pure Analysis Seminar, University of St Andrews, April 2018
An introduction to inhomogeneous attractors
Pure Postgraduate Seminar, University of St Andrews, April 2018
An introduction to iterated function systems
Postgraduate Interdisciplinary Mathematics Symposium, The Burn, Glen Esk, Februrary 2018
Dimension of inhomogeneous self-conformal and self-affine sets
School of Mathematics and Statistics Research Day, University of St Andrews, January 2018
Sequential Monte Carlo in population dynamics
Master's Defense, St Andrews, April 2016
Teaching
I enjoy teaching and received Associate Fellowship of the Higher Education Academy (AFHEA). At the University of St Andrews, three students kindly nominated me for the 'Best Postgraduate Tutor' teaching award. I have also designed courses for and worked with The Brilliant Club and First Chances Fife to promote wider access to higher education in the UK.