Gradient descent

Optimization · Formula · Appears in 2 lessons

θt+1=θt−η∇θL(θt)\theta_{t+1} = \theta_t - \eta \nabla_{\theta} L(\theta_t)

Step downhill: subtract a scaled gradient from the parameters and repeat. The entire difficulty is in the step size — too large and it diverges, too small and it never arrives.

Symbols

θ\theta
The parameters being optimised.
η\eta
The learning rate, the step size.
∇θL\nabla_{\theta} L
The gradient of the loss with respect to the parameters.
Esc
↑↓ navigate↵ open? shortcuts

Keyboard shortcuts

Press Esc to close

Anywhere

⌘K
Search and commands
/
Search
?
This sheet
Esc
Close

Reading a lesson

J
Next lesson
K
Previous lesson
B
Bookmark