Papers › Prospect Pruning: Finding Trainable Weights at Initialization using Meta-Gradients

Prospect Pruning: Finding Trainable Weights at Initialization using Meta-Gradients

16 Feb 2022ICLR 2022 4arXiv:2202.08132archive 2025-07-28

Milad Alizadeh, Shyam A. Tailor, Luisa M Zintgraf, Joost van Amersfoort, Sebastian Farquhar, Nicholas Donald Lane, Yarin Gal

Pruning neural networks at initialization would enable us to find sparse models that retain the accuracy of the original network while consuming fewer computational resources for training and inference. However, current methods are insufficient to enable this optimization and lead to a large degradation in model performance. In this paper, we identify a fundamental limitation in the formulation of current methods, namely that their saliency criteria look at a single step at the start of training without taking into account the trainability of the network. While pruning iteratively and gradually has been shown to improve pruning performance, explicit consideration of the training stage that will immediately follow pruning has so far been absent from the computation of the saliency criterion. To overcome the short-sightedness of existing methods, we propose Prospect Pruning (ProsPr), which uses meta-gradients through the first few steps of optimization to determine which weights to prune. ProsPr combines an estimate of the higher-order effects of pruning on the loss and the optimization trajectory to identify the trainable sub-network. Our method achieves state-of-the-art pruning performance on a variety of vision classification tasks, with less data and in a single shot compared to existing pruning-at-initialization methods.

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conv1x1 mil-ad/prospr/models/resnet_custom.py official repository ran · our draft was wrong MIT (permissive) · d9def42110729a85 · report
conv3x3 mil-ad/prospr/models/resnet_custom.py official repository ran · our draft was wrong MIT (permissive) · 160bb14bd76201b4 · report
apply_masks_with_hooks mil-ad/prospr/prospr/utils.py official repository unverified MIT (permissive) · 87ed2acbb021de28 · report
attach_masks_as_parameter mil-ad/prospr/prospr/utils.py official repository unverified MIT (permissive) · d1b161cee5bff7e5 · report
create_logdir mil-ad/prospr/utils.py official repository unverified MIT (permissive) · 4ba948355d6b2b2f · report
functional_sgd mil-ad/prospr/prospr/prospr.py official repository unverified MIT (permissive) · 2e0a7ab17059596d · report
get_cifar10 mil-ad/prospr/datasets.py official repository unverified MIT (permissive) · 035a3c7ada3cd3eb · report
get_cifar100 mil-ad/prospr/datasets.py official repository unverified MIT (permissive) · e953f0a585a2f2d9 · report
get_imagenet mil-ad/prospr/datasets.py official repository unverified MIT (permissive) · 6bc530d5e9c4de0a · report
pruning_filter_factory mil-ad/prospr/prospr/utils.py official repository unverified MIT (permissive) · 7b2200bb55802830 · report
resnet18 mil-ad/prospr/models/resnet_custom.py official repository unverified MIT (permissive) · 75ac27c2c68e8305 · report
unconcatenate mil-ad/prospr/utils.py official repository unverified MIT (permissive) · ebcb887f8a78c073 · report

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