Summary

September 9, 2025 · View on GitHub

This Universal Dependencies (UD) Japanese treebank is based on the definition of UD Japanese convention described in the UD documentation. The original sentences are from `Balanced Corpus of Contemporary Written Japanese'(BCCWJ).

Introduction

The Japanese UD treebank contains the sentences from BCCWJ [1] https://clrd.ninjal.ac.jp/bccwj/en/ with BCCWJ-DepPara[2] annotation.

The word units is based on Short Unit Word in BCCWJ [1]. We prepared conversion rules from BCCWJ-DepPara to UD_Japanese v2.1 guidelines [3][4].

Recovering data

The data is provided in the CoNLL format, but original texts are stripped off due to the license issue.

The corpus is obtained by running the following command:

./merge/merge.sh -c BCCWJ_CORE_FILE

where BCCWJ_CORE_FILE denotes the file of BCCWJ core file (core_SUW.txt) the script requires Python (3.x)

or

The BCCWJ DVD edition purchaser can download the data with the original text from https://bccwj-data.ninjal.ac.jp/

Spliting

Each data set contains UD annotations for the following parts in BCCWJ

training: annotation B, C, D, E subsets development: annotation A subset test: annotation A subset

See also https://github.com/masayu-a/BCCWJ-ANNOTATION-ORDER

Citation

You are encouraged to cite the following paper when you refer to the Universal Dependencies Japanese Treebank.

Asahara, M., Kanayama, H., Tanaka, T., Miyao, Y., Uematsu, S., Mori, S., Matsumoto, Y., Omura, M., & Murawaki, Y. (2018). Universal Dependencies Version 2 for Japanese. In LREC-2018.

Acknowledgments

The original treebank was provided by:

  • National Instutite for Japanese Language and Linguistics, Japan

The corpus was converted by:

  • Mai Omura
  • Masayuki Asahara

through discussion and validation with

  • Hiroshi Kanayama
  • Yusuke Miyao
  • Takaaki Tanaka
  • Yuji Matsumoto
  • Shinsuke Mori
  • Sumire Uematsu
  • Yugo Murawaki
  • Kaoru Ito
  • Taishi Chika

This work was supported by JSPS KAKENHI Grants Numbers JP17H00917 and NINJAL Annotation Project.

License

See file LICENSE.txt

Reference

[1] Maekawa, K., Yamazaki, M., Ogiso, T., Maruyama, T., Ogura, H., Kashino, W., Koiso, H., Yamaguchi, M., Tanaka, M. & Den, Y. (2014). Balanced corpus of contemporary written Japanese. Language resources and evaluation, 48(2), 345-371. [2] Asahara, M., & Matsumoto, Y. (2016). Bccwj-deppara: A syntactic annotation treebank on the ‘Balanced Corpus of Contemporary Written Japanese’. In Proceedings of the 12th Workshop on Asian Language Resources (ALR12) (pp. 49-58). [3] Tanaka, T., Miyao, Y., Asahara, M., Uematsu, S., Kanayama, H., Mori, S., & Matsumoto, Y. (2016). Universal Dependencies for Japanese. In LREC-2016. [4] Asahara, M., Kanayama, H., Tanaka, T., Miyao, Y., Uematsu, S., Mori, S., Matsumoto, Y., Omura, M., & Murawaki, Y. (2018). Universal Dependencies Version 2 for Japanese. In LREC-2018.

Changelog 2022-11-01 v2.11

  • Update v2.10 to v2.11 2022-05-01 v2.10
  • Update v2.9 to v2.10 2021-11-01 v2.9
  • Update v2.8 to v2.9 2021-05-01 v2.8
  • Update v2.7 to v2.8 2020-11-01 v2.7
  • Update v2.4 to v2.7 2019-05-01 v2.4
  • Update v2.3 to v2.4. 2018-11-01 v2.3
  • Update v2.2 to v2.3. 2018-03-28 v2.2
  • Initial release in Universal Dependencies.

=== Machine-readable metadata ================================================= Data available since: UD v2.2 License: CC BY-NC-SA 4.0 Includes text: no Parallel: no Genre: news nonfiction fiction blog web Lemmas: not available UPOS: converted from manual XPOS: not available Features: not available Relations: converted from manual Contributors: Omura, Mai; Asahara, Masayuki; Miyao, Yusuke; Tanaka, Takaaki; Kanayama, Hiroshi; Matsumoto, Yuji; Mori, Shinsuke; Uematsu, Sumire; Murawaki, Yugo Contributing: elsewhere Contact: masayu-a@ninjal.ac.jp