Asked about Batch size, schedules and regularisation in practice

Why AdamW rather than Adam with L2 regularisation?

An answer that works

Adam rescales gradients per parameter, so an L2 term in the loss does not act like true weight decay. AdamW applies decay directly to the weights, decoupled from the gradient scaling.

Reading an answer is not being able to give one. The section that teaches this is Batch size, schedules and regularisation in practice, 4 hours of Backpropagation.

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