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Training & Fine-tuningMedium· Maximal Update Parameterization· Hyperparameter Tuning· Scaling

What is μP and what problem does it solve?

μP ensures that activation magnitudes and gradient update sizes remain Θ(1) per coordinate regardless of the model width. By choosing specific initialization scales (1/√nin) and per-layer Adam learning rates (proportional to 1/nin), optimal hyperparameters discovered on a small proxy model can be transferred to a much larger scale without the need for additional re-tuning.

Code playground (Python)