On the Universal Approximation Property of Deep Fully Convolutional Neural Networks

Ting Lin; Zuowei Shen; Qianxiao Li

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arXiv · 2211.14047

On the Universal Approximation Property of Deep Fully Convolutional Neural Networks

Ting Lin·Zuowei Shen·Qianxiao Li

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Abstract

We study the approximation of shift-invariant or equivariant functions by deep fully convolutional networks from the dynamical systems perspective. We prove that deep residual fully convolutional networks and their continuous-layer counterpart can achieve universal approximation of these symmetric functions at constant channel width. Moreover, we show that the same can be achieved by non-residual variants with at least 2 channels in each layer and convolutional kernel size of at least 2. In addition, we show that these requirements are necessary, in the sense that networks with fewer channels or smaller kernels fail to be universal approximators.

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Ting Lin, Zuowei Shen, Qianxiao Li. 2022-11-25. On the Universal Approximation Property of Deep Fully Convolutional Neural Networks. https://arxiv.org/abs/2211.14047

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