Papers › DER: Dynamically Expandable Representation for Class Incremental Learning

DER: Dynamically Expandable Representation for Class Incremental Learning

31 Mar 2021CVPR 2021 1arXiv:2103.16788archive 2025-07-28

Shipeng Yan, Jiangwei Xie, Xuming He

We address the problem of class incremental learning, which is a core step towards achieving adaptive vision intelligence. In particular, we consider the task setting of incremental learning with limited memory and aim to achieve better stability-plasticity trade-off. To this end, we propose a novel two-stage learning approach that utilizes a dynamically expandable representation for more effective incremental concept modeling. Specifically, at each incremental step, we freeze the previously learned representation and augment it with additional feature dimensions from a new learnable feature extractor. This enables us to integrate new visual concepts with retaining learned knowledge. We dynamically expand the representation according to the complexity of novel concepts by introducing a channel-level mask-based pruning strategy. Moreover, we introduce an auxiliary loss to encourage the model to learn diverse and discriminate features for novel concepts. We conduct extensive experiments on the three class incremental learning benchmarks and our method consistently outperforms other methods with a large margin.

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ClassErrorMeter Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository ran MIT (permissive) · 9f4e9833f2b84b8d · report
GradualWarmupScheduler Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository ran MIT (permissive) · 59a549e22e134aef · report
extract_features Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository ran MIT (permissive) · 3df51f2e829fae0e · report
random_selection Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository ran MIT (permissive) · 655d09e23b2af00d · report
select_examplars Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository ran fingerprinted MIT (permissive) · 3fd7e4aeb10eb4da · report
update_classes_mean Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository ran MIT (permissive) · c1c1a3649ab6dc82 · report
IncModel Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository unverified MIT (permissive) · 555fea3dd6290bee · report
IncrementalLearner Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository unverified MIT (permissive) · 14b065dca3ad5ccd · report
MemorySize Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository unverified MIT (permissive) · 6fa0e1315b22f977 · report
finetune_last_layer Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository unverified MIT (permissive) · d9536cea4ed511c1 · report
herding Rhyssiyan/DER-ClassIL.pytorch/inclearn/models/incmodel.py official repository unverified MIT (permissive) · 60a5b69027a3fe6f · report

Tasks

Class Incremental LearningIncremental LearningNovel Conceptsclass-incremental learning

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Incremental Learning CIFAR-100 - 50 classes + 10 steps of 5 classes DER(Standard ResNet-18) Average Incremental Accuracy 72.45 #3 of 13 Archive leaderboard report
Incremental Learning CIFAR-100 - 50 classes + 10 steps of 5 classes DER(Modified ResNet-32) Average Incremental Accuracy 66.36 #7 of 13 Archive leaderboard report
Incremental Learning CIFAR-100 - 50 classes + 2 steps of 25 classes DER (w/o P) Average Incremental Accuracy 74.61 #3 of 4 Archive leaderboard report
Incremental Learning CIFAR-100 - 50 classes + 5 steps of 10 classes DER(Standard ResNet-18) Average Incremental Accuracy 72.60 #3 of 15 Archive leaderboard report
Incremental Learning CIFAR-100 - 50 classes + 5 steps of 10 classes DER(Modified Res-32) Average Incremental Accuracy 67.60 #7 of 15 Archive leaderboard report
Incremental Learning CIFAR-100-B0(5steps of 20 classes) DER(w/o P) Average Incremental Accuracy 76.80 #4 of 10 Archive leaderboard report
Incremental Learning CIFAR100-B0(10steps of 10 classes) DER(ResNet-18) Average Incremental Accuracy 74.64 #4 of 6 Archive leaderboard report
Incremental Learning CIFAR100B020Step(5ClassesPerStep) DER(ResNet-18) Average Incremental Accuracy 73.98 #4 of 5 Archive leaderboard report
Incremental Learning CIFAR100B050S(2ClassesPerStep) DER(ResNet-18) Average Incremental Accuracy 72.05 #1 of 1 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER w/o Pruning # M Params 116.89 #3 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER w/o Pruning Average Incremental Accuracy 68.84 #3 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER w/o Pruning Average Incremental Accuracy Top-5 88.17 #3 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER w/o Pruning Final Accuracy 60.16 #3 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER w/o Pruning Final Accuracy Top-5 82.86 #3 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER Average Incremental Accuracy 66.73 #6 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER Average Incremental Accuracy Top-5 87.08 #6 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER Final Accuracy 58.62 #6 of 10 Archive leaderboard report
Incremental Learning ImageNet - 10 steps DER Final Accuracy Top-5 81.89 #6 of 10 Archive leaderboard report
Incremental Learning ImageNet-100 - 50 classes + 10 steps of 5 classes DER Average Incremental Accuracy 77.73 #2 of 5 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER w/o Pruning # M Params 112.27 #6 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER w/o Pruning Average Incremental Accuracy 77.18 #6 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER w/o Pruning Average Incremental Accuracy Top-5 93.23 #6 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER w/o Pruning Final Accuracy 66.70 #6 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER w/o Pruning Final Accuracy Top-5 87.52 #6 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER Average Incremental Accuracy 76.12 #8 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER Average Incremental Accuracy Top-5 92.79 #8 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER Final Accuracy 66.07 #8 of 13 Archive leaderboard report
Incremental Learning ImageNet100 - 10 steps DER Final Accuracy Top-5 88.38 #8 of 13 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

Pruning

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