arXiv Machine Learning By Yimiao Yu, Florentin Guth

Localizing Transfer Between Memorization Tasks

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The paper investigates how pre‑training on random input‑output mappings (memorization tasks) can transfer to downstream tasks. It discovers two unexpected patterns: equivalent transfer, where each pre‑training epoch saves roughly one fine‑tuning epoch, and non‑equivalent transfer, where pre‑training on a mismatched task can be more efficient than training directly on the downstream task. Ablation studies reveal that transfer consists of a trivial magnitude‑driven effect in the last layer and a non‑trivial structure‑driven effect linked to covariance in other layers.

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