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# Formemes in English-Czech Deep Syntactic MT

**Authors:** Ondřej Dušek, [Zdeněk Žabokrtský](https://md.mova.elamur.ai/free/en/docs/papers/authors/zdenek-zabokrtsku/), [Martin Popel](https://md.mova.elamur.ai/free/en/docs/papers/authors/martin-popel/), Martin Majliš, [Michal Novák](https://md.mova.elamur.ai/free/en/docs/papers/authors/michal-novak/), [David Mareček](https://md.mova.elamur.ai/free/en/docs/papers/authors/david-marecek/) · **Year:** 2012 · **Venue:** Proceedings of the Seventh Workshop on Statistical Machine Translation **Link:** [aclanthology.org/W12-3132](https://aclanthology.org/W12-3132/) · **Licence:** [CC BY-NC-SA 3.0](https://creativecommons.org/licenses/by-nc-sa/3.0/) — summary only

[**15** citations](https://openalex.org/works?filter=cites:W2123962259) openalex · 2026-10-19[**13** citations in our library](https://md.mova.elamur.ai/free/en/docs/papers/cited-by/dusek-2012-formemes-english-czech-deep-syntactic/) of the 140673 papers whose bibliographies we read[Proceedings of the Seventh Workshop on Statistical Machine Translation](https://aclanthology.org/volumes/W12-31/)[licence](https://creativecommons.org/licenses/by-nc-sa/3.0/)

- [Publisher's page](https://aclanthology.org/W12-3132/)
- [PDF](https://aclanthology.org/W12-3132.pdf)
- [OpenAlex](https://openalex.org/W2123962259)

**Authors (6)**

1. [Ondřej Dušek](https://openalex.org/A5089653215) [Semantic Scholar](https://www.semanticscholar.org/author/2544049) · h 3 · 64 citations · 3 works
2. [Zdeněk Žabokrtský](https://openalex.org/A5088317432) [ORCID](https://orcid.org/0000-0001-8149-4054) · [Semantic Scholar](https://www.semanticscholar.org/author/2468732) · h 23 · 2057 citations · 167 works
3. [Martin Popel](https://openalex.org/A5083887502) [ORCID](https://orcid.org/0000-0002-3628-8419) · [Semantic Scholar](https://www.semanticscholar.org/author/3209310) · h 21 · 2689 citations · 110 works
4. [Martin Majliš](https://openalex.org/A5054035877) [Semantic Scholar](https://www.semanticscholar.org/author/2008448) · h 4 · 100 citations · 12 works
5. [Michal Novák](https://openalex.org/A5064242107) [ORCID](https://orcid.org/0000-0002-6052-7459) · [Semantic Scholar](https://www.semanticscholar.org/author/144299546) · h 10 · 416 citations · 63 works
6. [David Mareček](https://openalex.org/A5066030227) [ORCID](https://orcid.org/0000-0001-5327-488X) · [Semantic Scholar](https://www.semanticscholar.org/author/2536245) · h 17 · 848 citations · 142 works

Citations and author metrics from openalex (2026-10-19); authors with the same name are not always told apart.

## What it is about

A formeme is a short label for the surface morpho-syntax of a node in a deep dependency tree. It has three parts: a syntactic part of speech, an optional preposition or conjunction, and a form such as a case number or a finite-clause marker. The paper revises the formemes used in the TectoMT English-Czech system to reduce data sparsity and to make the two languages more consistent. The changes are: the syntactic part of speech replaces the semantic one; numerals and adjectives used as nouns get the value a noun would get in the same position; Czech nominal attributes are marked only when case-congruent; and prepositions are chosen from the part-of-speech filter, not from dependency labels. A candidate change is kept only if it increases the mutual information of formemes between Czech and English trees, which rose from 1.598 to 1.687. Several changes were dropped because they lowered it. In the downstream tests, Czech-to-Czech synthesis BLEU rose from 0.6818 to 0.7092, and English-Czech BLEU on the WMT12 test rose from 0.1190 to 0.1199, a small gain trained on half the data.

## Ideas

- I1. Value per meta token: give each meta token a short, readable value made of its coarse part of speech, its surface function word and its case or position (for example a subject noun, or a noun after "of"). This is the formeme idea for open problem 4, and it lets the encoder choose the surface form from the value alone.
- I2. A cheap gate before retraining: the paper scores a markup change by the mutual information between source and target values on aligned tokens, not by retraining the translation model. Use the same test on the Bible pairs in `tools/translate` to choose which function-word features to add, with counts kept in BTreeMap.
- I3. Keep a feature only when it raises the gate, as the paper drops changes that lower it. This mirrors the lexicon rule in open problem 2: a merge or a feature stays only if it lowers the residual.
- I4. Number words: the paper separates adjectival and nominal use of numerals (5 potatoes against Apollo 11). Count the same split for English and Hebrew number words in the Hebrew reader, which is the weakest part of the translator.

## For Mova

The code is `tools/translate/src/meta.rs` (the features) and `tools/translate/src/profile.rs` (the encoder that chooses surface forms). The paper is count-based and rule-based, so it fits Mova without change. Its gains are small, so each feature should be judged by the residual bits in exact mode, not by a single BLEU number.

Topics: [Part-of-speech tagging](https://md.mova.elamur.ai/free/en/docs/papers/topics/part-of-speech-tagging/) · [Machine translation](https://md.mova.elamur.ai/free/en/docs/papers/topics/machine-translation/)

## Cite

The paper itself, not this card. BibTeX from the library's record of the work.

```
@inproceedings{dusek2012formemes,
  title = {{Formemes in English-Czech Deep Syntactic MT}},
  author = {Dušek, Ondřej and Žabokrtský, Zdeněk and Popel, Martin and Majliš, Martin and Novák, Michal and Mareček, David},
  booktitle = {Proceedings of the Seventh Workshop on Statistical Machine Translation},
  year = {2012},
  url = {https://aclanthology.org/W12-3132/}
}
```

- [← previous Essays of John Dryden (ed. W. P. Ker): the Preface to Ovid's Epistles (1680) and the Dedication of the Aeneis (1697)](https://md.mova.elamur.ai/free/en/docs/papers/dryden-1900-essays-john-dryden/)
- [next → Inherently Reversible Grammars, Logic Programming and Computability](https://md.mova.elamur.ai/free/en/docs/papers/dymetman-1991-inherently-reversible-grammars-logic-programming/)
- [↑ back to Machine translation](https://md.mova.elamur.ai/free/en/docs/papers/mtrans/)

## References

27 references, 3 of them with a card of ours. ↗ leads to the work, «find» searches for one we have no id for yet.

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