Papers › Contrast to Divide: Self-Supervised Pre-Training for Learning with Noisy Labels

Contrast to Divide: Self-Supervised Pre-Training for Learning with Noisy Labels

25 Mar 2021arXiv:2103.13646archive 2025-07-28

Evgenii Zheltonozhskii, Chaim Baskin, Avi Mendelson, Alex M. Bronstein, Or Litany

The success of learning with noisy labels (LNL) methods relies heavily on the success of a warm-up stage where standard supervised training is performed using the full (noisy) training set. In this paper, we identify a "warm-up obstacle": the inability of standard warm-up stages to train high quality feature extractors and avert memorization of noisy labels. We propose "Contrast to Divide" (C2D), a simple framework that solves this problem by pre-training the feature extractor in a self-supervised fashion. Using self-supervised pre-training boosts the performance of existing LNL approaches by drastically reducing the warm-up stage's susceptibility to noise level, shortening its duration, and improving extracted feature quality. C2D works out of the box with existing methods and demonstrates markedly improved performance, especially in the high noise regime, where we get a boost of more than 27% for CIFAR-100 with 90% noise over the previous state of the art. In real-life noise settings, C2D trained on mini-WebVision outperforms previous works both in WebVision and ImageNet validation sets by 3% top-1 accuracy. We perform an in-depth analysis of the framework, including investigating the performance of different pre-training approaches and estimating the effective upper bound of the LNL performance with semi-supervised learning. Code for reproducing our experiments is available at https://github.com/ContrastToDivide/C2D

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CrossEntropyLoss ContrastToDivide/C2D/cross_entropy.py official repository ran · metamorphic tier: invariant MIT (permissive) · 0f9f54d5a814968a · report
_is_long ContrastToDivide/C2D/cross_entropy.py official repository ran · violated contract MIT (permissive) · 1fa7bb764f450073 · report
cross_entropy ContrastToDivide/C2D/cross_entropy.py official repository ran · fixture could not drive it MIT (permissive) · a8fa6f956d6f3de1 · report
linear_rampup ContrastToDivide/C2D/main_cifar.py official repository ran · honoured contract fingerprinted MIT (permissive) · 6944acdaa94d65ef · report
onehot ContrastToDivide/C2D/cross_entropy.py official repository ran · our draft was wrong MIT (permissive) · cfcd370121d1305f · report
smoothing ContrastToDivide/C2D/cross_entropy.py official repository ran · fixture could not drive it fingerprinted MIT (permissive) · 46e004362de7a8d3 · report
linear_rampup ContrastToDivide/C2D/Train_webvision.py official repository unverified MIT (permissive) · 371eb42215de99b0 · report

Tasks

Image ClassificationLearning with noisy labelsMemorization

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Image Classification CIFAR-10 (with noisy labels) C2D (ELR+ with SimCLR, ResNet-34) Accuracy (under 20% Sym. label noise) 96.74 ± 0.12 #2 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (ELR+ with SimCLR, ResNet-34) Accuracy (under 50% Sym. label noise) 95.55 ± 0.32 #2 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (ELR+ with SimCLR, ResNet-34) Accuracy (under 80% Sym. label noise) 93.11 ± 0.70 #2 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (ELR+ with SimCLR, ResNet-34) Accuracy (under 90% Sym. label noise) 89.30 ± 0.21 #2 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (ELR+ with SimCLR, ResNet-34) Accuracy (under 95% Sym. label noise) 80.21 ± 1.91 #2 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (DivideMix with SimCLR, ResNet-18) Accuracy (under 20% Sym. label noise) 96.23 ± 0.09 #4 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (DivideMix with SimCLR, ResNet-18) Accuracy (under 50% Sym. label noise) 95.15 ± 0.16 #4 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (DivideMix with SimCLR, ResNet-18) Accuracy (under 80% Sym. label noise) 94.30 ± 0.12 #4 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (DivideMix with SimCLR, ResNet-18) Accuracy (under 90% Sym. label noise) 93.42 ± 0.09 #4 of 4 Archive leaderboard report
Image Classification CIFAR-10 (with noisy labels) C2D (DivideMix with SimCLR, ResNet-18) Accuracy (under 95% Sym. label noise) 87.72 ± 2.21 #4 of 4 Archive leaderboard report
Image Classification Clothing1M ELR+ with C2D (ResNet-50) Accuracy 74.58 ± 0.15% #17 of 51 Archive leaderboard report
Image Classification mini WebVision 1.0 DivideMix with C2D (ResNet-50) ImageNet Top-1 Accuracy 78.57 ± 0.37 #14 of 47 Archive leaderboard report
Image Classification mini WebVision 1.0 DivideMix with C2D (ResNet-50) ImageNet Top-5 Accuracy 93.04 ± 0.10 #14 of 47 Archive leaderboard report
Image Classification mini WebVision 1.0 DivideMix with C2D (ResNet-50) Top-1 Accuracy 79.42 ± 0.34 #14 of 47 Archive leaderboard report
Image Classification mini WebVision 1.0 DivideMix with C2D (ResNet-50) Top-5 Accuracy 92.32 ± 0.33 #14 of 47 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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