An ETF view of Dropout regularization

Dor Bank; Raja Giryes

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arXiv · 1810.06049

An ETF view of Dropout regularization

Dor Bank·Raja Giryes

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Abstract

Dropout is a popular regularization technique in deep learning. Yet, the reason for its success is still not fully understood. This paper provides a new interpretation of Dropout from a frame theory perspective. By drawing a connection to recent developments in analog channel coding, we suggest that for a certain family of autoencoders with a linear encoder, optimizing the encoder with dropout regularization leads to an equiangular tight frame (ETF). Since this optimization is non-convex, we add another regularization that promotes such structures by minimizing the cross-correlation between filters in the network. We demonstrate its applicability in convolutional and fully connected layers in both feed-forward and recurrent networks. All these results suggest that there is indeed a relationship between dropout and ETF structure of the regularized linear operations.

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Dor Bank, Raja Giryes. 2018-10-14. An ETF view of Dropout regularization. https://arxiv.org/abs/1810.06049

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