The Lipschitz-Variance-Margin Tradeoff for Enhanced Randomized Smoothing

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Delattre, Blaise, Araujo, Alexandre, Barthélemy, Quentin, Allauzen, Alexandre
Natura: Preprint
Pubblicazione: 2023
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866910369920843776
author Delattre, Blaise
Araujo, Alexandre
Barthélemy, Quentin
Allauzen, Alexandre
author_facet Delattre, Blaise
Araujo, Alexandre
Barthélemy, Quentin
Allauzen, Alexandre
contents Real-life applications of deep neural networks are hindered by their unsteady predictions when faced with noisy inputs and adversarial attacks. The certified radius in this context is a crucial indicator of the robustness of models. However how to design an efficient classifier with an associated certified radius? Randomized smoothing provides a promising framework by relying on noise injection into the inputs to obtain a smoothed and robust classifier. In this paper, we first show that the variance introduced by the Monte-Carlo sampling in the randomized smoothing procedure estimate closely interacts with two other important properties of the classifier, \textit{i.e.} its Lipschitz constant and margin. More precisely, our work emphasizes the dual impact of the Lipschitz constant of the base classifier, on both the smoothed classifier and the empirical variance. To increase the certified robust radius, we introduce a different way to convert logits to probability vectors for the base classifier to leverage the variance-margin trade-off. We leverage the use of Bernstein's concentration inequality along with enhanced Lipschitz bounds for randomized smoothing. Experimental results show a significant improvement in certified accuracy compared to current state-of-the-art methods. Our novel certification procedure allows us to use pre-trained models with randomized smoothing, effectively improving the current certification radius in a zero-shot manner.
format Preprint
id arxiv_https___arxiv_org_abs_2309_16883
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle The Lipschitz-Variance-Margin Tradeoff for Enhanced Randomized Smoothing
Delattre, Blaise
Araujo, Alexandre
Barthélemy, Quentin
Allauzen, Alexandre
Machine Learning
Real-life applications of deep neural networks are hindered by their unsteady predictions when faced with noisy inputs and adversarial attacks. The certified radius in this context is a crucial indicator of the robustness of models. However how to design an efficient classifier with an associated certified radius? Randomized smoothing provides a promising framework by relying on noise injection into the inputs to obtain a smoothed and robust classifier. In this paper, we first show that the variance introduced by the Monte-Carlo sampling in the randomized smoothing procedure estimate closely interacts with two other important properties of the classifier, \textit{i.e.} its Lipschitz constant and margin. More precisely, our work emphasizes the dual impact of the Lipschitz constant of the base classifier, on both the smoothed classifier and the empirical variance. To increase the certified robust radius, we introduce a different way to convert logits to probability vectors for the base classifier to leverage the variance-margin trade-off. We leverage the use of Bernstein's concentration inequality along with enhanced Lipschitz bounds for randomized smoothing. Experimental results show a significant improvement in certified accuracy compared to current state-of-the-art methods. Our novel certification procedure allows us to use pre-trained models with randomized smoothing, effectively improving the current certification radius in a zero-shot manner.
title The Lipschitz-Variance-Margin Tradeoff for Enhanced Randomized Smoothing
topic Machine Learning
url https://arxiv.org/abs/2309.16883