8fd7f981e10b41330b618129afcaab2d-Supplemental.pdf

In this supplemental material, we provide additional details on the theory,the algorithms, and the experiments. In Section 2, we continue analyzing the population level difference between Trojaned and clean models, with a focus on the short-cuts. A boundaryoperatorona p-simplextakesallitsadjacent (p 1)-simplices.Inparticular,theboundary of an edges consists of its adjacent nodes; the boundary of a triangle consists of its three edges. More generally, the boundary of ap-chain is the formal sum1 of the boundary of all its elements, (c)= P σ c (c). Afterthereduction,thepivoting entries of the reduced matrix correspond to pairs of simplices.