19.11.2025, 13:00 Uhr
– Haus 9, Raum 0.17
Forschungsseminar Diskrete Spektraltheorie
Calculus of variations for nonlocal Sobolev–Bregman forms
Artur Rutkowski
Ibrahim Kaddouri (Universite Paris Saclay)
Motivated by the problem of detecting a change in the evolution of a
network, we consider the preferential attachment random graph model with
a time-dependent attachment function. Our goal is to detect whether the at-
tachment mechanism changed over time, based on a single snapshot of the
network and without directly observable information about the dynamics. We
cast this question as a hypothesis testing problem, where the null hypothe-
sis is a preferential attachment model with a constant affine attachment pa-
rameter δ0, and the alternative hypothesis is a preferential attachment model
where the affine attachment parameter changes from δ0 to δ1 at an unknown
changepoint time τn.