This research paper argues that relying on manually selected label token probabilities for classification in In-Context Learning (ICL) is suboptimal and proposes a novel method called Hidden Calibration, which utilizes centroid classifiers on the last hidden states of language models, leading to significant performance improvements in ICL.
In-context learning (ICL) can lead to miscalibration, especially in low-shot settings, and methods aimed at improving usability like fine-tuning and chain-of-thought prompting can further degrade calibration.