# Parsing as Pretraining

arXiv: https://arxiv.org/abs/2002.01685 · HTML: https://mlsanity.com/paper/2002.01685/

## Key facts

- Cited by 19 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 5 Feb 2020.

## Built on by (most cited first, 19 of 19)

- [Pre-Trained Models: Past, Present and Future](https://mlsanity.com/paper/2106.07139/) (2021)
- [Physics of Language Models: Part 1, Learning Hierarchical Language Structures](https://mlsanity.com/paper/2305.13673/) (2023)
- [Do Transformers Parse while Predicting the Masked Word?](https://mlsanity.com/paper/2303.08117/) (2023)
- [Probing for Constituency Structure in Neural Language Models](https://mlsanity.com/paper/2204.06201/) (2022)
- [Shaking Syntactic Trees on the Sesame Street: Multilingual Probing with Controllable Perturbations](https://mlsanity.com/paper/2109.14017/) (2021)
- [Potential and Limitations of LLMs in Capturing Structured Semantics: A Case Study on SRL](https://mlsanity.com/paper/2405.06410/) (2024)
- [Bertinho: Galician BERT Representations](https://mlsanity.com/paper/2103.13799/) (2021)
- [On the Evolution of Syntactic Information Encoded by BERT's Contextualized Representations](https://mlsanity.com/paper/2101.11492/) (2021)
- [Discontinuous Grammar as a Foreign Language](https://mlsanity.com/paper/2110.10431/) (2021)
- [Discontinuous Constituency and BERT: A Case Study of Dutch](https://mlsanity.com/paper/2203.01063/) (2022)
- [Topic Aware Probing: From Sentence Length Prediction to Idiom Identification how reliant are Neural Language Models on Topic?](https://mlsanity.com/paper/2403.02009/) (2024)
- [Structural Ambiguity and its Disambiguation in Language Model Based Parsers: the Case of Dutch Clause Relativization](https://mlsanity.com/paper/2305.14917/) (2023)
- [Construction Grammar and Language Models](https://mlsanity.com/paper/2308.13315/) (2023)
- [Assessment of Pre-Trained Models Across Languages and Grammars](https://mlsanity.com/paper/2309.11165/) (2023)
- [Understanding the Role of Input Token Characters in Language Models: How Does Information Loss Affect Performance?](https://mlsanity.com/paper/2310.17271/) (2023)
- [A Syntax-Injected Approach for Faster and More Accurate Sentiment Analysis](https://mlsanity.com/paper/2406.15163/) (2024)
- [Dancing in the syntax forest: fast, accurate and explainable sentiment analysis with SALSA](https://mlsanity.com/paper/2406.16071/) (2024)
- [Unsupervised and Few-shot Parsing from Pretrained Language Models](https://mlsanity.com/paper/2206.04980/) (2022)
- [Building Foundations for Natural Language Processing of Historical Turkish: Resources and Models](https://mlsanity.com/paper/2501.04828/) (2025)

## Abstract (arXiv)

Recent analyses suggest that encoders pretrained for language modeling capture certain morpho-syntactic structure. However, probing frameworks for word vectors still do not report results on standard setups such as constituent and dependency parsing. This paper addresses this problem and does full parsing (on English) relying only on pretraining architectures -- and no decoding. We first cast constituent and dependency parsing as sequence tagging. We then use a single feed-forward layer to directly map word vectors to labels that encode a linearized tree. This is used to: (i) see how far we can reach on syntax modelling with just pretrained encoders, and (ii) shed some light about the syntax-sensitivity of different word vectors (by freezing the weights of the pretraining network during training). For evaluation, we use bracketing F1-score and LAS, and analyze in-depth differences across representations for span lengths and dependency displacements. The overall results surpass existing sequence tagging parsers on the PTB (93.5%) and end-to-end EN-EWT UD (78.8%).
