Random Vector Functional Link Networks for Function Approximation on Manifolds

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Needell, Deanna, Nelson, Aaron A., Saab, Rayan, Salanevich, Palina, Schavemaker, Olov
Format: Preprint
Publié: 2020
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866914922902847488
author Needell, Deanna
Nelson, Aaron A.
Saab, Rayan
Salanevich, Palina
Schavemaker, Olov
author_facet Needell, Deanna
Nelson, Aaron A.
Saab, Rayan
Salanevich, Palina
Schavemaker, Olov
contents The learning speed of feed-forward neural networks is notoriously slow and has presented a bottleneck in deep learning applications for several decades. For instance, gradient-based learning algorithms, which are used extensively to train neural networks, tend to work slowly when all of the network parameters must be iteratively tuned. To counter this, both researchers and practitioners have tried introducing randomness to reduce the learning requirement. Based on the original construction of Igelnik and Pao, single layer neural-networks with random input-to-hidden layer weights and biases have seen success in practice, but the necessary theoretical justification is lacking. In this paper, we begin to fill this theoretical gap. We provide a (corrected) rigorous proof that the Igelnik and Pao construction is a universal approximator for continuous functions on compact domains, with approximation error decaying asymptotically like $O(1/\sqrt{n})$ for the number $n$ of network nodes. We then extend this result to the non-asymptotic setting, proving that one can achieve any desired approximation error with high probability provided $n$ is sufficiently large. We further adapt this randomized neural network architecture to approximate functions on smooth, compact submanifolds of Euclidean space, providing theoretical guarantees in both the asymptotic and non-asymptotic forms. Finally, we illustrate our results on manifolds with numerical experiments.
format Preprint
id arxiv_https___arxiv_org_abs_2007_15776
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle Random Vector Functional Link Networks for Function Approximation on Manifolds
Needell, Deanna
Nelson, Aaron A.
Saab, Rayan
Salanevich, Palina
Schavemaker, Olov
Machine Learning
Information Theory
Probability
62M45
The learning speed of feed-forward neural networks is notoriously slow and has presented a bottleneck in deep learning applications for several decades. For instance, gradient-based learning algorithms, which are used extensively to train neural networks, tend to work slowly when all of the network parameters must be iteratively tuned. To counter this, both researchers and practitioners have tried introducing randomness to reduce the learning requirement. Based on the original construction of Igelnik and Pao, single layer neural-networks with random input-to-hidden layer weights and biases have seen success in practice, but the necessary theoretical justification is lacking. In this paper, we begin to fill this theoretical gap. We provide a (corrected) rigorous proof that the Igelnik and Pao construction is a universal approximator for continuous functions on compact domains, with approximation error decaying asymptotically like $O(1/\sqrt{n})$ for the number $n$ of network nodes. We then extend this result to the non-asymptotic setting, proving that one can achieve any desired approximation error with high probability provided $n$ is sufficiently large. We further adapt this randomized neural network architecture to approximate functions on smooth, compact submanifolds of Euclidean space, providing theoretical guarantees in both the asymptotic and non-asymptotic forms. Finally, we illustrate our results on manifolds with numerical experiments.
title Random Vector Functional Link Networks for Function Approximation on Manifolds
topic Machine Learning
Information Theory
Probability
62M45
url https://arxiv.org/abs/2007.15776