Optimization without Backpropagation

Code

• github.com/gbelouze/forward-gradient
  OfficialIn papernone★ 8

Abstract

Forward gradients have been recently introduced to bypass backpropagation in autodifferentiation, while retaining unbiased estimators of true gradients. We derive an optimality condition to obtain best approximating forward gradients, which leads us to mathematical insights that suggest optimization in high dimension is challenging with forward gradients. Our extensive experiments on test functions support this claim.

Reproductions