Comparing Neural Network Parsers for a Less-resourced and Morphologically-rich Language: Amharic Dependency Parser
What it is about
The paper compares four off-the-shelf neural dependency parsers (UDPipe, jPTDP, UUParser, Turku) on the Amharic UD treebank, which has about 1,074 manually annotated sentences. Evaluation is ten-fold cross-validation, since the data is too small for a fixed split. The best result is UDPipe with a LAS of 83.79, rising to 85.26 when pretrained fastText vectors are added. The authors then run the pipeline from raw text: word segmentation drops from about 98% to about 80%, tagging falls from 93–95% to 74–77% with predicted segmentation, and attachment falls with it. Their conclusion is that the segmentation of clitics, done before tagging, is the bottleneck for a small-data parser, and that a joint model with morphological tags is a promising direction.
Ideas
- I1. Report the parser in two numbers: with gold segmentation and from raw text, with the drop attributed to each stage. For
tools/hboandgparse, measure LAS on the MACULA or PTNK trees with gold segments and with the segmenter's output, so that a loss is traced to the segmenter and not to the parser. - I2. Use ten-fold cross-validation on the small Hebrew treebanks (the same sentences in every fold, grouped by book or source) as the decision protocol for
gparsechanges, so that a small held-out set is not spent on every comparison. - I3. Character models help where the type-token ratio is high (the paper's jPTDP gain is largest on this kind of language): test a character-level input for the unpointed Hebrew path, against the word-only input, on the same folds.
For Mova
I1 is a reporting rule for tools/hbo (segmenter then gparse) and for treebanks/hbo/ptnk. I2 is an evaluation protocol for gparse in treebanks/hbo/. I3 is an experiment for the unpointed mode of tools/hbo, and a reason to keep the segmenter's tables visible in its output. The paper is non-commercial: only the summary above is used, and nothing from the text or the treebank is carried into a release.
Cite
@inproceedings{seyoum2020comparing,
title = {{Comparing Neural Network Parsers for a Less-resourced and Morphologically-rich Language: Amharic Dependency Parser}},
author = {Seyoum, Binyam Ephrem and Miyao, Yusuke and Mekonnen, Baye Yimam},
booktitle = {Proceedings of the first workshop on Resources for African Indigenous Languages},
year = {2020},
url = {https://aclanthology.org/2020.rail-1.5/}
}References
- Andor, D., Alberti, C., Weiss, D., Severyn, A., Presta, A., Ganchev, K., Petrov, S., and Collins, M. (2016). Globally Normalized Transition-Based Neural Networks. Association for Computational Linguistics, arXiv preprint arXiv:1603.06042. ↗
- Bohnet, B., McDonald, R., Simoes, G., Andor, D., Pitler, E., and Maynez, J. (2018). Morphosyntactic Tagging with a Meta-BiLSTM Model over Context Sensitive Token Encodings. In Proceedings of the 56 th Annual Meeting of the Association for Computational Linguistics (Long Papers), pages 2642–2652, Melbourne, Australia. Association for Computational Linguistics. find
- Che, W., Liu, Y., Wang, Y., Zheng, B., and Liu, T. (2018). Towards Better UD Parsing: Deep Contextualized Word Embeddings, Ensemble, and Treebank Concatenation. In Proceedings of the CoNLL 2018 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies, pages 55–64. find our card
- Chen, D. and Manning, C. D. (2014). A Fast and Accurate Dependency Parser using Neural Networks. In Proceedings of the 2014 Conference on Empirical Methods in Natural Language Processing (EMNLP), pages 740– 750, Doha, Qatar. find our card
- de Lhoneux, M., Shao, Y., Basirat, A., Kiperwasser, E., Stymne, S., Goldberg, Y., and Nivre, J. (2017). From raw text to universal dependencies-look, no tags! In Proceedings of the CoNLL 2017 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies, pages 207–217. find our card
- Dehdari, J., Tounsi, L., and van Genabith, J. (2011). Morphological Features for Parsing Morphologically-rich Languages: A Case of Arabic. In Proceedings of the 2nd Workshop on Statistical Parsing of Morphologically-Rich Languages (SPMRL 2011), pages 12–21, Dublin, Ireland. Association for Computational Linguistics. find our card
- Dozat, T. and Manning, C. D. (2017). Deep Biaffine Attention for Neural Dependency Parsing. In ICLR2017. find our card
- Dozat, T., Qi, P., and Manning, C. D. (2017). Stanford’s Graph-based Neural Dependency Parser at the CoNLL 2017 Shared Task. (2016):20–30. find our card
- Dyer, C., Ballesteros, M., Ling, W., Matthews, A., and Smith, N. A. (2015). Transition-Based Dependency Parsing with Stack Long Short-Term Memory. In Proceedings of the 53rd Annual Meeting of the Association for Computational Linguistics and the 7 th International Joint Conference on Natural Language Processing, pages 334–343, Beijing, China. Association for Computational Linguistics. find our card
- Dyer, C., Kuncoro, A., Ballesteros, M., and Smith, N. A. (2016). Recurrent Neural Network Grammars. In Proc. of NAACL. find
- Goldberg, Y. (2017). Neural Network Methods for Natural Language Processing. In Synthesis Lectures on Human Language Technologies, volume 10, pages 1–282. Morgan & Claypool Publishers series. find
- Grave, E., Bojanowski, P., Gupta, P., Joulin, A., and Mikolov, T. (2018). Learning Word Vectors for 157 Languages. In Proceedings of the International Conference on Language Resources and Evaluation (LREC 2018), pages 1–5. find
- Habash, N. Y. (2010). Introduction to Arabic Natural Language Processing. Synthesis Lectures on Human Language Technologies, 3(1):1–187. find
- Kanerva, J., Ginter, F., Miekka, N., Leino, A., and Salakoski, T. (2018). Turku Neural Parser Pipeline : An End-to-End System for the CoNLL 2018 Shared Task. In Proceedings of the CoNLL 2018 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies, pages 133–142. find our card
- Kiperwasser, E. and Goldberg, Y. (2016). Simple and Accurate Dependency Parsing Using Bidirectional LSTM Feature Representations. Transactions of the Association for Computational Linguistics, 4:313–327. find our card
- Kübler, S., McDonald, R., and Nivre, J. (2009). Dependency Parsing. Synthesis Lectures on Human Language Technologies, 34(1):1–127. find
- Kuncoro, A., Ballesteros, M., Kong, L., Dyer, C., Neubig, G., and Smith, N. A. (2017). What Do Recurrent Neural Network Grammars Learn About Syntax? arXiv preprint arXiv:1611.05774. ↗
- Lavelli, A. (2016). Comparing State-of-the-art Dependency Parsers on the Italian Stanford Dependency Treebank. CLiC it, pages 173–178. find
- Mcdonald, R., Crammer, K., and Pereira, F. (2005). Online Large-Margin Training of Dependency Parsers. pages 91–98. find our card
- Nguyen, D. Q. and Verspoor, K. (2018). An improved neural network model for joint POS tagging and dependency parsing. In Proceedings of the CoNLL 2018 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies, pages 81–91. find our card
- Nivre, J. (2008). Algorithms for Deterministic Incremental Dependency Parsing. Computational Linguistics, 34(4):513–553. find our card
- Nivre, J. (2014). Universal Dependencies for Swedish. In The Fifth Swedish Language Technology Conference (Sltc), pages 1579–1585. find
- Seyoum, B. E., Miyao, Y., and Mekonnen, B. Y. (2018). Universal Dependencies for Amharic. In Nicoletta Calzolari, et al., editors, Proceedings of the Eleventh International Conference on Language Resources and Evaluation (LREC 2018), pages 2216–2222, Miyazaki, Japan. European Language Resources Association (ELRA). find our card
- Smith, A., de Lhoneux, M., Stymne, S., and Nivre, J. (2018). An Investigation of the Interactions Between Pre-Trained Word Embeddings, Character Models and POS Tags in Dependency Parsing. In Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing, pages 2711–2720, Brussels, Belgium. Association for Computational Linguistics. find
- Straka, M., Hajič, J., and Straková, J. (2016). UDPipe: Trainable Pipeline for Processing CoNLL-U Files Performing Tokenization, Morphological Analysis, POS Tagging and Parsing. In Proceedings of LREC 2016, pages 4290–4297. find our card
- Straka, M., Straková, J., and Hajič, J. (2017). Prague at EPE 2017: The UDPipe System. In Proceedings of the 2017 Shared Task on Extrinsic Parser Evaluation at the Fourth International Conference on Dependency Linguistics and the 15 th International Conference on Parsing Technologies, pages 65–74, Pisa (Italy). Association for Computational Linguistics (ACL). find
- Straková, J., Straka, M., and Hajič, J. (2014). Open-Source Tools for Morphology, Lemmatization, POS Tagging and Named Entity Recognition. In Proceedings of the 52 nd Annual Meeting of the Association for Computational Linguistics: System Demonstrations, pages 13–18, Baltimore, Maryland USA. Association for Computational Linguistics. find
- Tsarfaty, R., Seddah, D., Goldberg, Y., Kübler, S., Candito, M., Foster, J., Versley, Y., Rehbein, I., and Tounsi, L. (2010). Statistical parsing of morphologically rich languages (SPMRL): what, how and whither. In Proceedings of the NAACL HLT 2010 First Workshop on Statistical Parsing of Morphologically-Rich Languages, pages 1–12, Los Angeles, California. Association for Computational Linguistics. find
- Zeman, D., Popel, M., Straka, M., Hajic, J., Nivre, J., Ginter, F., Luotolahti, J., Pyysalo, S., Petrov, S., Potthast, M., Tyers, F., Badmaeva, E., Gokirmak, M., Nedoluzhko, A., Cinkova, S., Hajic jr., J., Hlavacova, J., Kettnerová, V., Uresova, Z., Kanerva, J., Ojala, S., Missilä, A., Manning, C. D., Schuster, S., Reddy, S., Taji, D., Habash, N., Leung, H., de Marneffe, M.-C., Sanguinetti, M., Simi, M., Kanayama, H., DePaiva, V., Droganova, K., Martı́nez Alonso, H., Çöltekin, Ç., Sulubacak, U., Uszkoreit, H., Macketanz, V., Burchardt, A., Harris, K., Marheinecke, K., Rehm, G., Kayadelen, T., Attia, M., Elkahky, A., Yu, Z., Pitler, E., Lertpradit, S., Mandl, M., Kirchner, J., Alcalde, H. F., Strnadová, J., Banerjee, E., Manurung, R., Stella, A., Shimada, A., Kwak, S., Mendonca, G., Lando, T., Nitisaroj, R., and Li, J. (2017). CoNLL 2017 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies. In Proceedings of the CoNLL 2017 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies, pages 1–19. Association for Computational Linguistics. find our card
- Zeman, D., HajiË, J., Popel, M., Potthast, M., Straka, M., Ginter, F., Nivre, J., and Petrov, S. (2018). CoNLL 2018 Shared Task : Multilingual Parsing from Raw Text to Universal Dependencies. In Proceedings of the CoNLL 2018 Shared Task: Multilingual Parsing from Raw Text to Universal Dependencies, pages 1–21, Brussels, Belgium. Association for Computational Linguistics. find our card
- Zhang, Y. and Nivre, J. (2011). Transition-based Dependency Parsing with Rich Non-local Features. In Proceedings of the 49 th Annual Meeting of the Association for Computational Linguistics: short papers, pages 188– 193. Association for Computational Linguistics. find
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