Title
Finite Depth and Width Corrections to the Neural Tangent Kernel
Abstract
We prove the precise scaling, at finite depth and width, for the mean and variance of the neural tangent kernel (NTK) in a randomly initialized ReLU network. The standard deviation is exponential in the ratio of network depth to width. Thus, even in the limit of infinite overparameterization, the NTK is not deterministic if depth and width simultaneously tend to infinity. Moreover, we prove that for such deep and wide networks, the NTK has a non-trivial evolution during training by showing that the mean of its first SGD update is also exponential in the ratio of network depth to width. This is sharp contrast to the regime where depth is fixed and network width is very large. Our results suggest that, unlike relatively shallow and wide networks, deep and wide ReLU networks are capable of learning data-dependent features even in the so-called lazy training regime.
Year
Venue
Keywords
2020
ICLR
Neural Tangent Kernel, Finite Width Corrections, Random ReLU Net, Wide Networks, Deep Networks
DocType
Citations 
PageRank 
Conference
0
0.34
References 
Authors
14
2
Name
Order
Citations
PageRank
Boris Hanin1474.04
Mihai Nica210711.33