Machine Learning Research

arXiv 2026

Log-Likelihood, Simpson's Paradox, and the Detection of Machine-Generated Text

T. Kempton, Viktor Drobnyi, Maeve Madigan, and Stuart Burrell. arXiv preprint, 2026.

We collect evidence from other papers showing that likelihood-based detectors of machine-generated text really target the overconfidence of instruction-tuned models. We show that this overconfidence does not present itself uniformly across hidden space, and that the aggregation of token-level scores in most detectors significantly weakens the signal. We introduce a local calibration step before averaging which dramatically improves the performance of state-of-the-art likelihood-based detectors.

ICLR 2026

DMAP: A Distribution Map for Text

T. Kempton, Julia Rozanova, Parameswaran Kamalaruban, Maeve Madigan, Karolina Wresilo, Yoann Launay, David Sutton, and Stuart Burrell.

Introduces DMAP, a statistically rigorous way to visualise where a text sits in the next-token probability distribution of a language model.

AAAI 2026 Workshop

Emergent Bias and Fairness in Multi-Agent Decision Systems

Maeve Madigan, Parameswaran Kamalaruban, Glenn Moynihan, T. Kempton, David Sutton, and Stuart Burrell. Accepted at the Workshop on Agentic AI in Financial Services at the AAAI 2026 conference in Singapore.

Studies fairness evaluation in multi-agent predictive systems and shows how emergent bias can arise from collective system behavior rather than any single component.

Submitted

Fairness-Aware Test-Time Prompt Tuning

Yoann Launay, Parameswaran Kamalaruban, T. Kempton, Stuart Burrell, and David Sutton. Submitted.

Introduces a fairness-aware test-time adaptation method for vision-language models that reduces bias under distribution shift by tuning prompts to improve target performance while suppressing spurious attribute signals.