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arXiv · 1708.06257

A Flow Model of Neural Networks

Zhen Li·Zuoqiang Shi
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Abstract

Based on a natural connection between ResNet and transport equation or its characteristic equation, we propose a continuous flow model for both ResNet and plain net. Through this continuous model, a ResNet can be explicitly constructed as a refinement of a plain net. The flow model provides an alternative perspective to understand phenomena in deep neural networks, such as why it is necessary and sufficient to use 2-layer blocks in ResNets, why deeper is better, and why ResNets are even deeper, and so on. It also opens a gate to bring in more tools from the huge area of differential equations.

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Zhen Li, Zuoqiang Shi. 2017-08-21. A Flow Model of Neural Networks. https://arxiv.org/abs/1708.06257

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