Ensemble-Based Unsupervised Discontinuous Constituency Parsing by Tree Averaging
<|reference_start|>Ensemble-Based Unsupervised Discontinuous Constituency Parsing by Tree Averaging: We address unsupervised discontinuous constituency parsing, where we observe a high variance in the performance of the only previous model. We propose to build an ensemble of different runs of the existing discontinuous parser by averaging the predicted trees, to stabilize and boost performance. To begin with, we provide comprehensive computational complexity analysis (in terms of P and NP-complete) for tree averaging under different setups of binarity and continuity. We then develop an efficient exact algorithm to tackle the task, which runs in a reasonable time for all samples in our experiments. Results on three datasets show our method outperforms all baselines in all metrics; we also provide in-depth analyses of our approach.<|reference_end|>
@article{shayegh2024tree-averaging,
    title={Tree-Averaging Algorithms for Ensemble-Based Unsupervised Discontinuous
  Constituency Parsing},
    author={Behzad Shayegh, Yuqiao Wen, Lili Mou},
    journal={2024. In Proceedings of the 62nd Annual Meeting of the Association
  for Computational Linguistics (Volume 1: Long Papers), pages 15135-15156,
  Bangkok, Thailand. Association for Computational Linguistics},
    year={2024},
    doi={10.18653/v1/2024.acl-long.808},
    archivePrefix={arXiv},
    eprint={2403.00143},
    primaryClass={cs.CL cs.AI cs.LG}
}