super-weights-in-llms-and-the-failure-of-selective-training-13a495a8·1 events·first seen Aliases: Super Weights in LLMs and the Failure of Selective Training
A new arXiv paper investigates Super Weights — individual LLM parameters whose removal catastrophically degrades performance — and finds that their apparent importance does not translate into trainability. Training Super Weights in isolation (100 to 8,192 parameters) collapses accuracy to random-guessing on OLMo-1B and OLMo-7B, while training an equal number of randomly chosen parameters in the same layers improves over baseline. LoRA, which applies structured low-rank updates across entire layers, succeeds with only 0.16% of parameters, and constraining LoRA updates at Super Weight coordinates yields no benefit. The findings challenge the assumption that parameter importance implies parameter trainability and suggest effective fine-tuning requires structured decompositions over full layers rather than targeted sparse updates.