In plain words: A big language model was taught to follow instructions using just 1,000 carefully chosen question-and-answer examples, with no extra feedback training. In human tests its answers tied with or beat GPT-4's 43% of the time, suggesting nearly all knowledge is picked up earlier.
Abstract
Large language models are trained in two stages: (1) unsupervised pretraining from raw text, to learn general-purpose representations, and (2) large scale instruction tuning and reinforcement learning, to better align to end tasks and user preferences. We measure the relative importance of these two stages by training LIMA, a 65B parameter LLaMa language model fine-tuned with the standard supervised loss on only 1,000 carefully curated prompts and responses, without any reinforcement learning or human preference modeling. LIMA demonstrates remarkably strong performance, learning to follow specific response formats from only a handful of examples in the training data, including complex queries that range from planning trip itineraries to speculating about alternate history. Moreover, the model tends to generalize well to unseen tasks that did not appear in the training data. In a controlled human study, responses from LIMA are either equivalent or strictly preferred to GPT-4 in 43% of cases; this statistic is as high as 58% when compared to Bard and 65% versus DaVinci003, which was trained with human feedback. Taken together, these results strongly suggest that almost all knowledge in large language models is learned during pretraining, and only limited instruction tuning data is necessary to teach models to produce high quality output.
Chunting Zhou, Pengfei Liu, Puxin Xu, Srini Iyer, Jiao Sun, Yuning Mao, Xuezhe Ma, Avia Efrat, Ping Yu, Lili Yu, Susan Zhang, Gargi Ghosh, et al.
arXiv:2305.11206 · cs.CL, cs.AI, cs.LG · submitted May 18, 2023
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What I missed: How does the superficial alignment hypothesis related to model size (they only investigate disjoint aspects on 7B vs 65B llama models). Since the paper focuses on data quality, I would have expected an annotation guideline.
Still, I think the paper is an excellent read.