Unsupervised Learning on Neural Network Outputs: with Application in Zero-shot Learning

Yao Lu

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arXiv · 1506.00990

Unsupervised Learning on Neural Network Outputs: with Application in Zero-shot Learning

Yao Lu

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Abstract

The outputs of a trained neural network contain much richer information than just an one-hot classifier. For example, a neural network might give an image of a dog the probability of one in a million of being a cat but it is still much larger than the probability of being a car. To reveal the hidden structure in them, we apply two unsupervised learning algorithms, PCA and ICA, to the outputs of a deep Convolutional Neural Network trained on the ImageNet of 1000 classes. The PCA/ICA embedding of the object classes reveals their visual similarity and the PCA/ICA components can be interpreted as common visual features shared by similar object classes. For an application, we proposed a new zero-shot learning method, in which the visual features learned by PCA/ICA are employed. Our zero-shot learning method achieves the state-of-the-art results on the ImageNet of over 20000 classes.

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Yao Lu. 2015-06-02. Unsupervised Learning on Neural Network Outputs: with Application in Zero-shot Learning. https://arxiv.org/abs/1506.00990

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