Accelerating Backpropagation through Dynamic Self-adaptation

Standard backpropagation and many procedures derived from it use the steepest-descent method to minimize a cost function. In this paper, we present a new genetic algorithm, dynamic self-adaptation, to accelerate steepest descent as it is used in iterative procedures. The underlying idea is to take the learning rate of the previous step, to increase and decrease it slightly, to evaluate the cost function for both new values of the learning rate, and to choose the one that gives the lower value of the cost function. In this way, the algorithm adapts itself locally to the cost function landscape. We present a convergence proof, estimate the convergence rate, and test the algorithm on several hard problems. As compared to standard backpropagation, the convergence rate can be improved by several orders of magnitude. Furthermore, dynamic self-adaptation can also be applied to several parameters simultaneously, such as the learning rate and momentum.