On the Global Convergence of Gradient Descent for multi-layer ResNets in
the mean-field regime
- URL: http://arxiv.org/abs/2110.02926v1
- Date: Wed, 6 Oct 2021 17:16:09 GMT
- Title: On the Global Convergence of Gradient Descent for multi-layer ResNets in
the mean-field regime
- Authors: Zhiyan Ding and Shi Chen and Qin Li and Stephen Wright
- Abstract summary: First-order methods find the global optimum in the globalized regime.
We show that if the ResNet is sufficiently large, with depth width depending on the accuracy and confidence levels, first-order methods can find optimization that fit the data.
- Score: 19.45069138853531
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Finding the optimal configuration of parameters in ResNet is a nonconvex
minimization problem, but first-order methods nevertheless find the global
optimum in the overparameterized regime. We study this phenomenon with
mean-field analysis, by translating the training process of ResNet to a
gradient-flow partial differential equation (PDE) and examining the convergence
properties of this limiting process. The activation function is assumed to be
$2$-homogeneous or partially $1$-homogeneous; the regularized ReLU satisfies
the latter condition. We show that if the ResNet is sufficiently large, with
depth and width depending algebraically on the accuracy and confidence levels,
first-order optimization methods can find global minimizers that fit the
training data.
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