Juncai He

## Institution:

The University of Texas at Austin

## Time:

Monday, January 10, 2022 - 4:00pm to 5:00pm

## Location:

Zoom: https://uci.zoom.us/j/97796361534

The low dimensional manifold hypothesis posits that the data found in many applications, such as those involving natural images, lie (approximately) on low dimensional manifolds embedded in a high dimensional Euclidean space. In this setting, a typical neural network defines a function that takes a finite number of vectors in the embedding space as input. However, one often needs to consider evaluating the optimized network at points outside the training distribution. This talk considers the cases where the training data are distributed in a linear subspace of $\mathbb R^d$. We derive estimates on the variation of the learning function, defined by a neural network, in the direction transversal to the subspace. We study the potential regularization effects associated with the network's depth and noise in the codimension of the data manifold. We also present the additional side effect in training due to the noise.