GPT-2 Small
Feature statistics
×no parameters
A mean and a standard deviation for each of the 768 features, measured over the validation set before training and saved with the checkpoint.
- out
- [2 mean, standard deviation, 768 features]
Explanation
They are measured once, over at most 1,000 validation batches in each process, on valid positions only, with the variance clamped from below at 10⁻⁴. They are tensors the trainer holds and writes into the checkpoint, not parameters: nothing updates them. Their values in the released checkpoint were not read.
Sources2
Contextual evidence
The feature statistics are a mean and a standard deviation per feature over valid positions of the validation set, the variance clamped at 10⁻⁴; features are standardized with them.
The implementation, pinned at revision e18c42acdfb7, not yet public
Contextual evidence
Training computes the statistics once before the first step; they are saved with the checkpoint.
The implementation, pinned at revision e18c42acdfb7, not yet public