All the datasets are publicly available and can be found here:

PIQA: https://huggingface.co/datasets/ybisk/piqa
Hellaswag: https://huggingface.co/datasets/Rowan/hellaswag
Winogrande: https://huggingface.co/datasets/allenai/winogrande
ARC-Easy: https://leaderboard.allenai.org/arc_easy/submissions/get-started
Wikitextv2: https://huggingface.co/datasets/mindchain/wikitext2
PG-19: https://github.com/google-deepmind/pg19
