MATRIX MOMENTUM FOR PRACTICAL NATURAL GRADIENT LEARNING
An on-line learning rule, based on the introduction of a matrix momentum term, is presented, aimed at alleviating the computational costs of standard natural gradient learning. The new rule, natural gradient matrix momentum, is analysed in the case of two-layer feed-forward neural network learning via methods of statistical physics. It appears to provide a practical algorithm that performs as well as standard natural gradient descent in both the transient and asymptotic regimes but with a hugely reduced complexity.