(Neural Computation. 2002;14:1723-1738.)
© 2002 The MIT Press
Fast Curvature Matrix-Vector Products for Second-Order Gradient Descent
Nicol N. Schraudolph
nic{at}inf.ethz.ch, IDSIA, Galleria 2, 6928 Manno, Switzerland, and Institute of Computational Science, ETH Zentrum, 8092 Zürich, Switzerland
We propose a generic method for iteratively approximating various second-order gradient stepsNewton, Gauss-Newton, Levenberg-Marquardt, and natural gradientin linear time per iteration, using special curvature matrix-vector products that can be computed in O(n). Two recent acceleration techniques for on-line learning, matrix momentum and stochastic meta-descent (SMD), implement this approach. Since both were originally derived by very different routes, this offers fresh insight into their operation, resulting in further improvements to SMD.
Copyright © 2002 by The MIT Press.