Papers › TruthfulQA: Measuring How Models Mimic Human Falsehoods

TruthfulQA: Measuring How Models Mimic Human Falsehoods

8 Sep 2021ACL 2022 5arXiv:2109.07958archive 2025-07-28

Stephanie Lin, Jacob Hilton, Owain Evans

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.

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data_to_dict sylinrl/truthfulqa/truthfulqa/evaluate.py official repository ran · our draft was wrong Apache-2.0 (permissive) · 679c0af24337099d · report
format_frame sylinrl/truthfulqa/truthfulqa/evaluate.py official repository ran · our draft was wrong Apache-2.0 (permissive) · 18c6154c3dcf6170 · report

Tasks

Language ModelingLanguage ModellingMisconceptionsQuestion AnsweringQuestion GenerationTruthfulQA

Datasets

Introduced by this paper, per the archive.

TruthfulQA

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Question Answering TruthfulQA GPT-2 1.5B % info 89.84 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B % true 29.50 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B % true (GPT-judge) 29.87 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B BLEU -4.91 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B BLEURT -0.25 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B MC1 0.22 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B MC2 0.39 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-2 1.5B ROUGE -9.41 #15 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B % info 97.55 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B % true 20.44 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B % true (GPT-judge) 20.56 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B BLEU -17.38 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B BLEURT -0.56 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B MC1 0.21 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B MC2 0.33 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-3 175B ROUGE -17.75 #17 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B % info 89.96 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B % true 26.68 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B % true (GPT-judge) 27.17 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B BLEU -7.58 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B BLEURT -0.31 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B MC1 0.20 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B MC2 0.36 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA GPT-J 6B ROUGE -11.35 #19 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B % info 64.50 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B % true 53.86 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B % true (GPT-judge) 53.24 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B BLEU -0.16 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B BLEURT 0.08 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B MC1 0.19 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B MC2 0.35 #20 of 33 Archive leaderboard report
Question Answering TruthfulQA UnifiedQA 3B ROUGE 1.76 #20 of 33 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

AdamAttentionAttention DropoutBPECosine AnnealingDense ConnectionsDiscriminative Fine-TuningDropoutGPT-2GPT-3Layer NormalizationLinear LayerLinear Warmup With Cosine AnnealingMulti-Head AttentionResidual ConnectionSoftmaxWeight Decay

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