[edit]
Zeroth-Order Topological Insights into Iterative Magnitude Pruning
Proceedings of Topological, Algebraic, and Geometric Learning Workshops 2022, PMLR 196:6-16, 2022.
Abstract
Modern-day neural networks are famously large, yet also highly redundant and compressible; there exist numerous pruning strategies in the deep learning literature that yield over 90% sparser sub-networks of fully-trained, dense architectures while still maintaining their original accuracies. Amongst these many methods though – thanks to its conceptual simplicity, ease of implementation, and efficacy – Iterative Magnitude Pruning (IMP) dominates in practice and is the de facto baseline to beat in the pruning community. However, theoretical explanations as to why a simplistic method such as IMP works at all are few and limited. In this work, we leverage persistent homology to show that IMP inherently encourages retention of those weights which preserve topological information in a trained network. Subsequently, we also provide bounds on how much different networks can be pruned while perfectly preserving their zeroth order topological features, and present a modified version of IMP to do the same.