Verb Conjugation in Transformers Is Determined by Linear Encodings of Subject Number
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Abstract (arXiv)
Deep architectures such as Transformers are sometimes criticized for having uninterpretable "black-box" representations. We use causal intervention analysis to show that, in fact, some linguistic features are represented in a linear, interpretable format. Specifically, we show that BERT's ability to conjugate verbs relies on a linear encoding of subject number that can be manipulated with predictable effects on conjugation accuracy. This encoding is found in the subject position at the first layer and the verb position at the last layer, but distributed across positions at middle layers, particularly when there are multiple cues to subject number.
Key facts. Cited by 12 papers in the map (data through 14 Oct 2026). Builds on 21 of its 30 references that are in the map. First posted on arXiv 23 Oct 2023.
Builds on
21 of 30 references.
References · 21
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9 more
- 2021Causal Analysis of Syntactic Agreement Mechanisms in Neural Language Modelscited by 131
- 2018What Is One Grain of Sand in the Desert? Analyzing Individual Neurons in Deep NLP Modelscited by 124
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- 2022Probing for the Usage of Grammatical Numbercited by 59
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Citing papers per year: 2024: 4; 2025: 2; 2026: 6.
12 papers.
- 2024ReFT: Representation Finetuning for Language Modelscited by 197
- 2024CausalGym: Benchmarking causal interpretability methods on linguistic taskscited by 46
- 2025Bayesian Teaching Enables Probabilistic Reasoning in Large Language Modelscited by 37
- 2024Language Models as Models of Languagecited by 24
- 2025LinguaLens: Towards Interpreting Linguistic Mechanisms of Large Language Models via Sparse Auto-Encodercited by 14
- 2024Philosophy of Cognitive Science in the Age of Deep Learningcited by 5
- 2026Humans and transformer LMs: Abstraction drives language learningcited by 2
- 2026The Grammar of Transformers: A Systematic Review of Interpretability Research on Syntactic Knowledge in Language Modelscited by 1
- 2026Refusal Beyond a Single Direction: A Preliminary Comparison of Diff-in-Means and INLPcited by 1
- 2026Filling in the Mechanisms: How do LMs Learn Filler-Gap Dependencies under Developmental Constraints?cited by 0
- 2026Causal Interventions on Continuous Variables: A Case Study on Verb Bias in Steering Vectors for In-Context Learningcited by 0
- 2026Cognitive Convergence: Deep Similarities Between Large Language Models and Human Cognitioncited by 0
- 2026Cognitive Convergence: Deep Similarities Between Large Language Models and Human Cognition28 Jul 2026
- 2026Refusal Beyond a Single Direction: A Preliminary Comparison of Diff-in-Means and INLP11 Jun 2026
- 2026Causal Interventions on Continuous Variables: A Case Study on Verb Bias in Steering Vectors for In-Context Learning28 May 2026
- 2026Filling in the Mechanisms: How do LMs Learn Filler-Gap Dependencies under Developmental Constraints?15 Apr 2026
- 2026Humans and transformer LMs: Abstraction drives language learning18 Mar 2026
- 2026The Grammar of Transformers: A Systematic Review of Interpretability Research on Syntactic Knowledge in Language Models9 Jan 2026
- 2025Bayesian Teaching Enables Probabilistic Reasoning in Large Language Models21 Mar 2025
- 2025LinguaLens: Towards Interpreting Linguistic Mechanisms of Large Language Models via Sparse Auto-Encoder27 Feb 2025
- 2024Language Models as Models of Language13 Aug 2024
- 2024Philosophy of Cognitive Science in the Age of Deep Learning7 May 2024
- 2024ReFT: Representation Finetuning for Language Models4 Apr 2024
- 2024CausalGym: Benchmarking causal interpretability methods on linguistic tasks19 Feb 2024