We give an efficient algorithm which can obtain a relative error approximation to the spectral norm of a matrix, combining the power iteration method with some techniques from matrix reconstruction which use random sampling.
@article{arxiv.1104.2076,
title = {A Note On Estimating the Spectral Norm of A Matrix Efficiently},
author = {Malik Magdon-Ismail},
journal= {arXiv preprint arXiv:1104.2076},
year = {2011}
}