Cognitive Dissonance: Why Do Language Model Outputs Disagree with Internal Representations of Truthfulness?

Kevin Liu, Stephen Casper, Dylan Hadfield-Menell, Jacob Andreas


Abstract
Neural language models (LMs) can be used to evaluate the truth of factual statements in two ways: they can be either queried for statement probabilities, or probed for internal representations of truthfulness. Past work has found that these two procedures sometimes disagree, and that probes tend to be more accurate than LM outputs. This has led some researchers to conclude that LMs “lie’ or otherwise encode non-cooperative communicative intents. Is this an accurate description of today’s LMs, or can query–probe disagreement arise in other ways? We identify three different classes of disagreement, which we term confabulation, deception, and heterogeneity. In many cases, the superiority of probes is simply attributable to better calibration on uncertain answers rather than a greater fraction of correct, high-confidence answers. In some cases, queries and probes perform better on different subsets of inputs, and accuracy can further be improved by ensembling the two.
Anthology ID:
2023.emnlp-main.291
Volume:
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing
Month:
December
Year:
2023
Address:
Singapore
Editors:
Houda Bouamor, Juan Pino, Kalika Bali
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
4791–4797
Language:
URL:
https://aclanthology.org/2023.emnlp-main.291
DOI:
10.18653/v1/2023.emnlp-main.291
Bibkey:
Cite (ACL):
Kevin Liu, Stephen Casper, Dylan Hadfield-Menell, and Jacob Andreas. 2023. Cognitive Dissonance: Why Do Language Model Outputs Disagree with Internal Representations of Truthfulness?. In Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing, pages 4791–4797, Singapore. Association for Computational Linguistics.
Cite (Informal):
Cognitive Dissonance: Why Do Language Model Outputs Disagree with Internal Representations of Truthfulness? (Liu et al., EMNLP 2023)
Copy Citation:
PDF:
https://aclanthology.org/2023.emnlp-main.291.pdf
Video:
 https://aclanthology.org/2023.emnlp-main.291.mp4