aiqbench analysis
This research demonstrates that the numerical range of confidence scales in LLMs is not neutral, showing that a 0–20 scale significantly improves metacognitive efficiency compared to the standard 0–100 format. The study reveals that model outputs are heavily discretized around round numbers, a bias that degrades performance when boundary compression occurs but persists regardless of range regularity. These findings establish confidence scale design as a critical experimental variable for accurately evaluating uncertainty in large language models.
Rescaling Confidence: What Scale Design Reveals About LLM Metacognition
arXiv:2603.09309v3 Announce Type: replace Abstract: Verbalized confidence, in which LLMs report a numerical certainty score, is widely used to estimate uncertainty in black-box settings, yet the confidence scale itself (typically 0--100) is rarely examined. We show that this design choice is not neutral. Across six LLMs and three datasets, verbalized confidence is heavily discretized, with more than 78\% of responses concentrating on just three round-number values. To investigate this phenomenon, we systematically manipulate confidence scales along three dimensions: granularity, boundary placement, and range regularity, and evaluate metacognitive sensitivity using $meta\text{-}d'$. We find that a 0--20 scale consistently improves metacognitive efficiency over the standard 0--100 format, while boundary compression degrades performance and round-number preferences persist even under irregular ranges. These results demonstrate that confidence scale design directly affects the quality of verbalized uncertainty and should be treated as a first-class experimental variable in LLM evaluation.
Abstract:Verbalized confidence, in which LLMs report a numerical certainty score, is widely used to estimate uncertainty in black-box settings, yet the confidence scale itself (typically 0--100) is rarely examined. We show that this design choice is not neutral. Across six LLMs and three datasets, verbalized confidence is heavily discretized, with more than 78\% of responses concentrating on just three round-number values. To investigate this phenomenon, we systematically manipulate confidence scales along three dimensions: granularity, boundary placement, and range regularity, and evaluate metacognitive sensitivity using $meta\text{-}d'$. We find that a 0--20 scale consistently improves metacognitive efficiency over the standard 0--100 format, while boundary compression degrades performance and round-number preferences persist even under irregular ranges. These results demonstrate that confidence scale design directly affects the quality of verbalized uncertainty and should be treated as a first-class experimental variable in LLM evaluation.
Artificial Intelligence (cs.AI)
arXiv:2603.09309 [cs.AI]
(or arXiv:2603.09309v3 [cs.AI] for this version)
https://doi.org/10.48550/arXiv.2603.09309 Focus to learn more arXiv-issued DOI via DataCite
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