Momentum-based acceleration of stochastic gradient descent (SGD) is widely used in deep learning. We propose the quasi-hyperbolic momentum algorithm (QHM) as an extremely simple alteration of momentum SGD, averaging a plain SGD step with a momentum step. We describe numerous connections to and identities with other algorithms, and we characterize the set of two-state optimization algorithms that QHM can recover. Finally, we propose a QH variant of Adam called QHAdam, and we empirically demonstrate that our algorithms lead to significantly improved training in a variety of settings, including a new state-of-the-art result on WMT16 EN-DE. We hope that these empirical results, combined with the conceptual and practical simplicity of QHM and QHAdam, will spur interest from both practitioners and researchers. Code is immediately available.
Mix plain SGD and momentum (or do something similar with Adam) for great profit. The paper proposes simple modifications to SGD and Adam, called QH-variants, that can recover the “parent” method and a host of other optimization tricks. A variant of classical momentum which takes a weighted average of momentum and gradient update, and an evaluation of its relationships between other momentum based optimization schemes.