BIZNIQUE / CALCULUS / 47
Separate a noisy step from a better objective
Watch an illustrative disturbance change a gradient-descent path.
BIZNIQUE / CALCULUS / 47
Watch an illustrative disturbance change a gradient-descent path.
THE IDEA
The demo adds a deterministic oscillating disturbance to the exact gradient of a quadratic. It illustrates why individual steps can fluctuate even when an underlying objective is simple. Real stochastic gradients depend on sampling and data.
Observed update direction = gradient + disturbance
Noise can alter exploration and stability, but it does not guarantee escape from a poor region or convergence to a better result. Inspect trends and the actual evaluation objective.
TRY IT YOURSELF
Can a single rise in training loss prove that a stochastic optimiser is broken?
No. Stochastic updates can fluctuate; persistent behaviour, step size and evaluation conditions need to be examined.