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arXiv · 2207.09225

Similarity of Pre-trained and Fine-tuned Representations

Thomas Goerttler·Klaus Obermayer
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Abstract

In transfer learning, only the last part of the networks - the so-called head - is often fine-tuned. Representation similarity analysis shows that the most significant change still occurs in the head even if all weights are updatable. However, recent results from few-shot learning have shown that representation change in the early layers, which are mostly convolutional, is beneficial, especially in the case of cross-domain adaption. In our paper, we find out whether that also holds true for transfer learning. In addition, we analyze the change of representation in transfer learning, both during pre-training and fine-tuning, and find out that pre-trained structure is unlearned if not usable.

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Thomas Goerttler, Klaus Obermayer. 2022-07-19. Similarity of Pre-trained and Fine-tuned Representations. https://arxiv.org/abs/2207.09225

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