The Tunnel Effect: Building Data Representations in Deep Neural Networks
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Abstract (arXiv)
Deep neural networks are widely known for their remarkable effectiveness across various tasks, with the consensus that deeper networks implicitly learn more complex data representations. This paper shows that sufficiently deep networks trained for supervised image classification split into two distinct parts that contribute to the resulting data representations differently. The initial layers create linearly-separable representations, while the subsequent layers, which we refer to as textitthe tunnel, compress these representations and have a minimal impact on the overall performance. We explore the tunnel's behavior through comprehensive empirical studies, highlighting that it emerges early in the training process. Its depth depends on the relation between the network's capacity and task complexity. Furthermore, we show that the tunnel degrades out-of-distribution generalization and discuss its implications for continual learning.
Key facts. Cited by 34 papers in the map (data through 14 Oct 2026). Builds on 54 of its 72 references that are in the map. First posted on arXiv 31 May 2023.
Builds on
54 of 72 references.
References · 54
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- 2018Universal Transformerscited by 647
- 2019Deep Equilibrium Modelscited by 615
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- 2020What is being transferred in transfer learning?cited by 368
- 2016On the Expressive Power of Deep Neural Networkscited by 306
- 2019Intrinsic dimension of data representations in deep neural networkscited by 282
- 2020Do Wide and Deep Networks Learn the Same Things? Uncovering How Neural Network Representations Vary with Width and Depthcited by 245
- 2021A Geometric Analysis of Neural Collapse with Unconstrained Featurescited by 227
- 2020The large learning rate phase of deep learning: the catapult mechanismcited by 216
- 2018Deep learning generalizes because the parameter-function map is biased towards simple functionscited by 183
- 2019Complexity of Linear Regions in Deep Networkscited by 167
- 2020Anatomy of Catastrophic Forgetting: Hidden Representations and Task Semanticscited by 161
- 2021The Low-Rank Simplicity Bias in Deep Networkscited by 154
- 2020Adversarial Continual Learningcited by 142
- 2018Regularization Matters: Generalization and Optimization of Neural Nets v.s. their Induced Kernelcited by 131
- 2023Similarity of Neural Network Models: A Survey of Functional and Representational Measurescited by 131
- 2021Generalized Shape Metrics on Neural Representationscited by 112
- 2020What makes instance discrimination good for transfer learning?cited by 111
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- 2021On the Role of Neural Collapse in Transfer Learningcited by 100
- 2019Latent Replay for Real-Time Continual Learningcited by 97
- 2019Are All Layers Created Equal?cited by 94
- 2021Continual Learning in the Teacher-Student Setup: Impact of Task Similaritycited by 88
- 2015Representation Benefits of Deep Feedforward Networkscited by 86
- 2020Towards Learning a Universal Non-Semantic Representation of Speechcited by 84
- 2022Head2Toe: Utilizing Intermediate Representations for Better Transfer Learningcited by 83
- 2022How catastrophic can catastrophic forgetting be in linear regression?cited by 81
- 2021A Broad Study on the Transferability of Visual Representations with Contrastive Learningcited by 78
- 2019A Fine-Grained Spectral Perspective on Neural Networkscited by 68
- 2021Wide Neural Networks Forget Less Catastrophicallycited by 64
- 2022Limitations of Neural Collapse for Understanding Generalization in Deep Learningcited by 63
- 2019Universality and individuality in neural dynamics across large populations of recurrent networkscited by 61
- 2018Trellis Networks for Sequence Modelingcited by 52
- 2022Architecture Matters in Continual Learningcited by 46
- 2018Recurrent Stacking of Layers for Compact Neural Machine Translation Modelscited by 38
- 2017Transfer learning for music classification and regression taskscited by 37
- 2021Revisiting the Transferability of Supervised Pretraining: an MLP Perspectivecited by 36
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- 2022Understanding and Improving Transfer Learning of Deep Models via Neural Collapsecited by 24
- 2021Feature Learning and Signal Propagation in Deep Neural Networkscited by 18
50 most cited of 54 All 54 (JSON)
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