# Dependency distance minimization predicts compression

arXiv: https://arxiv.org/abs/2109.08900 · HTML: https://mlsanity.com/paper/2109.08900/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 14 of its 51 references that are in the map.
- First posted on arXiv 18 Sep 2021.

## Builds on (most cited first, 14 of 14)

- [Phonotactic Complexity and its Trade-offs](https://mlsanity.com/paper/2005.03774/) (2020)
- [The optimality of syntactic dependency distances](https://mlsanity.com/paper/2007.15342/) (2020)
- [Anti dependency distance minimization in short sequences. A graph theoretic approach](https://mlsanity.com/paper/1906.05765/) (2019)
- [How (Non-)Optimal is the Lexicon?](https://mlsanity.com/paper/2104.14279/) (2021)
- [Optimal coding and the origins of Zipfian laws](https://mlsanity.com/paper/1906.01545/) (2019)
- [The placement of the head that maximizes predictability. An information theoretic approach](https://mlsanity.com/paper/1705.09932/) (2017)
- [Minimum projective linearizations of trees in linear time](https://mlsanity.com/paper/2102.03277/) (2021)
- [The placement of the head that minimizes online memory: a complex systems approach](https://mlsanity.com/paper/1309.1939/) (2013)
- [The scarcity of crossing dependencies: a direct outcome of a specific constraint?](https://mlsanity.com/paper/1601.03210/) (2016)
- [Optimization models of natural communication](https://mlsanity.com/paper/1412.2486/) (2014)
- [Kauffman's adjacent possible in word order evolution](https://mlsanity.com/paper/1512.05582/) (2015)
- [Reply to the commentary "Be careful when assuming the obvious", by P. Alday](https://mlsanity.com/paper/1412.7186/) (2014)
- [Be Careful When Assuming the Obvious: Commentary on "The placement of the head that minimizes online memory: a complex systems approach"](https://mlsanity.com/paper/1408.4753/) (2014)
- [Towards a theory of word order. Comment on "Dependency distance: a new perspective on syntactic patterns in natural language" by Haitao Liu et al](https://mlsanity.com/paper/1706.04872/) (2017)

## Abstract (arXiv)

Dependency distance minimization (DDm) is a well-established principle of word order. It has been predicted theoretically that DDm implies compression, namely the minimization of word lengths. This is a second order prediction because it links a principle with another principle, rather than a principle and a manifestation as in a first order prediction. Here we test that second order prediction with a parallel collection of treebanks controlling for annotation style with Universal Dependencies and Surface-Syntactic Universal Dependencies. To test it, we use a recently introduced score that has many mathematical and statistical advantages with respect to the widely used sum of dependency distances. We find that the prediction is confirmed by the new score when word lengths are measured in phonemes, independently of the annotation style, but not when word lengths are measured in syllables. In contrast, one of the most widely used scores, i.e. the sum of dependency distances, fails to confirm that prediction, showing the weakness of raw dependency distances for research on word order. Finally, our findings expand the theory of natural communication by linking two distinct levels of organization, namely syntax (word order) and word internal structure.