3 papers
math.CO2026
Two Linear Programs are Better than One
Alexander E. Black, Christoph Hertrich, Stefan Kober +1
The extension complexity of a polytope is the minimum number of facets of a polytope that projects onto it. Motivated by the complexity of neural network…
math.CO2025
Arithmetic Circuits and Neural Networks for Regular Matroids
Christoph Hertrich, Stefan Kober, Georg Loho
We prove that there exist uniform -circuits of size to compute the basis generating polynomial of regular matroids on elements. By tropicalization, this…
cs.LG2025
Radius-Guided Post-Clustering for Shape-Aware, Scalable Refinement of k-Means Results
Stefan Kober
Traditional k-means clustering underperforms on non-convex shapes and requires the number of clusters k to be specified in advance. We propose a simple geometric enhancement: after…