Papers › Nested Collaborative Learning for Long-Tailed Visual Recognition

Nested Collaborative Learning for Long-Tailed Visual Recognition

29 Mar 2022CVPR 2022 1arXiv:2203.15359archive 2025-07-28

Jun Li, Zichang Tan, Jun Wan, Zhen Lei, Guodong Guo

The networks trained on the long-tailed dataset vary remarkably, despite the same training settings, which shows the great uncertainty in long-tailed learning. To alleviate the uncertainty, we propose a Nested Collaborative Learning (NCL), which tackles the problem by collaboratively learning multiple experts together. NCL consists of two core components, namely Nested Individual Learning (NIL) and Nested Balanced Online Distillation (NBOD), which focus on the individual supervised learning for each single expert and the knowledge transferring among multiple experts, respectively. To learn representations more thoroughly, both NIL and NBOD are formulated in a nested way, in which the learning is conducted on not just all categories from a full perspective but some hard categories from a partial perspective. Regarding the learning in the partial perspective, we specifically select the negative categories with high predicted scores as the hard categories by using a proposed Hard Category Mining (HCM). In the NCL, the learning from two perspectives is nested, highly related and complementary, and helps the network to capture not only global and robust features but also meticulous distinguishing ability. Moreover, self-supervision is further utilized for feature enhancement. Extensive experiments manifest the superiority of our method with outperforming the state-of-the-art whether by using a single model or an ensemble.

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NBOD_NCL_plus Bazinga699/NCL/lib/loss/loss.py official repository ran · our draft was wrong BSD-2-Clause (permissive) · 270dd46baf67536e · report
NIL_NBOD_plus Bazinga699/NCL/lib/loss/loss.py official repository ran · metamorphic tier: deterministic BSD-2-Clause (permissive) · 59b7f5f78d055951 · report

Tasks

Image ClassificationLong-tail Learning

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Long-tail Learning CIFAR-10-LT (ρ=100) NCL(ResNet32) Error Rate 15.3 #11 of 28 Archive leaderboard report
Long-tail Learning CIFAR-10-LT (ρ=50) NCL(ResNet32) Error Rate 13.2 #7 of 8 Archive leaderboard report
Long-tail Learning CIFAR-100-LT (ρ=100) NCL(ResNet32) Error Rate 46.7 #18 of 66 Archive leaderboard report
Long-tail Learning CIFAR-100-LT (ρ=50) NCL(ResNet32) Error Rate 43.2 #16 of 25 Archive leaderboard report
Long-tail Learning ImageNet-LT NCL(ResNeXt-50) Top-1 Accuracy 58.4 #21 of 69 Archive leaderboard report
Long-tail Learning ImageNet-LT NCL(ResNet-50) Top-1 Accuracy 57.4 #29 of 69 Archive leaderboard report
Long-tail Learning Places-LT NCL(ResNet-152) Top-1 Accuracy 41.5 #14 of 29 Archive leaderboard report
Long-tail Learning iNaturalist 2018 NCL(ResNet-50) Top-1 Accuracy 74.2% #19 of 43 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.

Methods

NCL

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