class chainer.optimizer_hooks.WeightDecay(rate)[source]

Optimizer/UpdateRule hook function for weight decay regularization.

This hook function adds a scaled parameter to the corresponding gradient. It can be used as a regularization.


rate (float) – Coefficient for the weight decay.

  • rate (float) – Coefficient for the weight decay.
  • timing (string) – Specifies when this hook should be called by the Optimizer/UpdateRule. Valid values are ‘pre’ (before any updates) and ‘post’ (after any updates).
  • call_for_each_param (bool) – Specifies if this hook is called for each parameter (True) or only once (False) by an optimizer to which this hook is registered. This function does not expect users to switch the value from default one, which is True.

New in version 4.0.0: The timing parameter.


__call__(rule, param)[source]

Call self as a function.


call_for_each_param = True
name = 'WeightDecay'
timing = 'pre'