Large-Scale Dataset Pruning in Adversarial Training through Data Importance Extrapolation
Björn Nieth, Thomas Altstidl, Leo Schwinn, Björn Eskofier
TL;DR
The paper tackles the challenge of high computational cost in adversarial training when large synthetic datasets are used. It introduces data importance extrapolation: estimating DU-based pruning scores for unseen data by averaging the scores of the $k$ nearest neighbors in a learned embedding space, enabling scalable pruning with expensive ranking methods. By applying this to DU and a new FP (frequency-based) pruning metric, the authors show robust and clean accuracy improvements under 50% pruning on large synthetic CIFAR-10 data, with class-balanced pruning often performing best. This data-centric pruning approach significantly improves the practicality of adversarial training with synthetic data, though it relies on extrapolation quality and suggests future work on richer data attribution methods.
Abstract
Their vulnerability to small, imperceptible attacks limits the adoption of deep learning models to real-world systems. Adversarial training has proven to be one of the most promising strategies against these attacks, at the expense of a substantial increase in training time. With the ongoing trend of integrating large-scale synthetic data this is only expected to increase even further. Thus, the need for data-centric approaches that reduce the number of training samples while maintaining accuracy and robustness arises. While data pruning and active learning are prominent research topics in deep learning, they are as of now largely unexplored in the adversarial training literature. We address this gap and propose a new data pruning strategy based on extrapolating data importance scores from a small set of data to a larger set. In an empirical evaluation, we demonstrate that extrapolation-based pruning can efficiently reduce dataset size while maintaining robustness.
