Research Group "Stochastic Algorithms and Nonparametric Statistics"

Research Seminar "Mathematical Statistics" Winter Semester 2026/2027

14.10.2026 Dr. Chloé Rouyer (Universität Potsdam)

21.10.2026 Prof. Dr. Kolyan Ray (Imperial College London)

28.10.2026 Dr. Nicolas Verzelen (INRAE, Université Montpellier )

04.11.2026 Prof. Dr. Mark Podolski (Universität Luxemburg)
HVP 11 a, R.313
11.11.2026 Prof. Dr. Simon Weißmann (Universität Mannheim)

18.11.2026 Prof. Dr. Botond Szabo (Bocconi University)

25.11.2026 Dr. Christoph von Tycowicz (Zuse Institute Berlin (ZIB))
Symmetry-preserving geodesic regression on Lie Groups for longitudinal medical imaging
Many medical imaging tasks require statistical modeling of continuous transformations, including longitudinal anatomical shape change and articulated skeletal motion. These transformations naturally live on Lie groups, where meaningful statistical analysis should respect group symmetries to remain invariant to arbitrary coordinate choices and reference frames. In this talk, I will present a geodesic regression framework on Lie groups for longitudinal imaging data. Common approaches rely on Riemannian metrics, but many Lie groups do not admit a metric fully compatible with the group structure. This mismatch breaks symmetry and leads to unstable regression estimates. We therefore introduce a non-metric, bi-invariant estimator that is equivariant under both left and right group actions. We evaluate the method on synthetic data and on an open-access clinical dataset of longitudinal knee joint configurations acquired for osteoarthritis research. The proposed approach yields stable trajectories and reproducible statistical conclusions, while state-of-the-art Riemannian methods exhibit sensitivity and instability. These results highlight the practical advantages of symmetry-preserving statistical modeling in longitudinal medical imaging studies.
02.12.2026 Dr. Hugo Cui (Laboratory of Orsay

09.12.2026 Prof. Dr. Yuta Koike (Tokyo University)
16.12.2026 Dr. Eardi Lila (University of Washington)
Geometric deep operator learning for inverse problems with functional data
06.01.2027 Prof. Dr. Claudia Strauch (Universiät Heidelberg)

13.01.2027

20.01.2027

27.01.2027 TRR Workshop: Statistical Inference for Complex Stochastic Systems
HVP 11 a, R.313
03.02.2027
10.02.2027 Prof. Dr. Alexander Kreiß (Universität Hildesheim)

17.02.2027



last reviewed: September 23, 2026 by Christine Schneider