Garamvölgyi Dániel: Graph rigidity and the maximum likelihood threshold

EGERVÁRY SZEMINÁRIUM

Absztrakt: The maximum likelihood threshold (MLT) is a graph parameter arising naturally in the study of Gaussian graphical models, a commonly used statistical model. Recently, Gross and Sullivant discovered a connection between the MLT of a graph and its rigidity matroid. Building on their observations, Bernstein et al. characterized the MLT of a graph in terms of the existence of so-called PSD stress matrices. In the talk I will give an introduction to these notions, as well as highlight some combinatorial open questions in the area.