TruthfulQA: Measuring How Models Mimic Human Falsehoods

Stephanie Lin, Jacob Hilton, Owain Evans


Abstract
We propose a benchmark to measure whether a language model is truthful in generating answers to questions. The benchmark comprises 817 questions that span 38 categories, including health, law, finance and politics. We crafted questions that some humans would answer falsely due to a false belief or misconception. To perform well, models must avoid generating false answers learned from imitating human texts. We tested GPT-3, GPT-Neo/J, GPT-2 and a T5-based model. The best model was truthful on 58% of questions, while human performance was 94%. Models generated many false answers that mimic popular misconceptions and have the potential to deceive humans. The largest models were generally the least truthful. This contrasts with other NLP tasks, where performance improves with model size. However, this result is expected if false answers are learned from the training distribution. We suggest that scaling up models alone is less promising for improving truthfulness than fine-tuning using training objectives other than imitation of text from the web.
Anthology ID:
2022.acl-long.229
Volume:
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
May
Year:
2022
Address:
Dublin, Ireland
Editors:
Smaranda Muresan, Preslav Nakov, Aline Villavicencio
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
3214–3252
Language:
URL:
https://aclanthology.org/2022.acl-long.229
DOI:
10.18653/v1/2022.acl-long.229
Bibkey:
Cite (ACL):
Stephanie Lin, Jacob Hilton, and Owain Evans. 2022. TruthfulQA: Measuring How Models Mimic Human Falsehoods. In Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 3214–3252, Dublin, Ireland. Association for Computational Linguistics.
Cite (Informal):
TruthfulQA: Measuring How Models Mimic Human Falsehoods (Lin et al., ACL 2022)
Copy Citation:
PDF:
https://aclanthology.org/2022.acl-long.229.pdf
Software:
 2022.acl-long.229.software.zip
Code
 sylinrl/truthfulqa +  additional community code
Data
TruthfulQA