In plain words: Big language models seem to gain abilities suddenly as they grow, but this study re-scores the same model outputs with different grading scales. With smooth scoring, performance rises gradually, so the sudden jumps come from how results are graded, not from real new skills.
Abstract · Are Emergent Abilities of Large Language Models a Mirage?
Recent work claims that large language models display emergent abilities, abilities not present in smaller-scale models that are present in larger-scale models. What makes emergent abilities intriguing is two-fold: their sharpness, transitioning seemingly instantaneously from not present to present, and their unpredictability, appearing at seemingly unforeseeable model scales. Here, we present an alternative explanation for emergent abilities: that for a particular task and model family, when analyzing fixed model outputs, emergent abilities appear due to the researcher's choice of metric rather than due to fundamental changes in model behavior with scale. Specifically, nonlinear or discontinuous metrics produce apparent emergent abilities, whereas linear or continuous metrics produce smooth, continuous predictable changes in model performance. We present our alternative explanation in a simple mathematical model, then test it in three complementary ways: we (1) make, test and confirm three predictions on the effect of metric choice using the InstructGPT/GPT-3 family on tasks with claimed emergent abilities; (2) make, test and confirm two predictions about metric choices in a meta-analysis of emergent abilities on BIG-Bench; and (3) show to choose metrics to produce never-before-seen seemingly emergent abilities in multiple vision tasks across diverse deep networks. Via all three analyses, we provide evidence that alleged emergent abilities evaporate with different metrics or with better statistics, and may not be a fundamental property of scaling AI models.
Rylan Schaeffer, Brando Miranda, Sanmi Koyejo
arXiv:2304.15004 · cs.AI, cs.LG · submitted Apr 28, 2023 · updated May 22, 2023
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The paper's claim is essentially "these metrics which appear to demonstrate emergence can be replaced by other metrics that also represent model behavior, but that do not have scale discontinuities, so emergence isn't a real phenomenon".
But an equally valid interpretation would be "none of these metrics actually capture the properties we are truly interested in". Which, given the complexity of what we are dealing with here, seems entirely reasonable. It's not like we suddenly learned how to accurately quantify performance at language tasks. The whole reason LLMs are so great in the first place is because traditional 'mechanical' language models suck so bad.