Meishan Zhang


2020

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DRTS Parsing with Structure-Aware Encoding and Decoding
Qiankun Fu | Yue Zhang | Jiangming Liu | Meishan Zhang
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics

Discourse representation tree structure (DRTS) parsing is a novel semantic parsing task which has been concerned most recently. State-of-the-art performance can be achieved by a neural sequence-to-sequence model, treating the tree construction as an incremental sequence generation problem. Structural information such as input syntax and the intermediate skeleton of the partial output has been ignored in the model, which could be potentially useful for the DRTS parsing. In this work, we propose a structural-aware model at both the encoder and decoder phase to integrate the structural information, where graph attention network (GAT) is exploited for effectively modeling. Experimental results on a benchmark dataset show that our proposed model is effective and can obtain the best performance in the literature.

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Cross-Lingual Semantic Role Labeling with High-Quality Translated Training Corpus
Hao Fei | Meishan Zhang | Donghong Ji
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics

Many efforts of research are devoted to semantic role labeling (SRL) which is crucial for natural language understanding. Supervised approaches have achieved impressing performances when large-scale corpora are available for resource-rich languages such as English. While for the low-resource languages with no annotated SRL dataset, it is still challenging to obtain competitive performances. Cross-lingual SRL is one promising way to address the problem, which has achieved great advances with the help of model transferring and annotation projection. In this paper, we propose a novel alternative based on corpus translation, constructing high-quality training datasets for the target languages from the source gold-standard SRL annotations. Experimental results on Universal Proposition Bank show that the translation-based method is highly effective, and the automatic pseudo datasets can improve the target-language SRL performances significantly.

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Cross-Lingual Dependency Parsing via Self-Training
Meishan Zhang | Yue Zhang
Proceedings of the 19th Chinese National Conference on Computational Linguistics

Recent advances of multilingual word representations weaken the input divergences across languages, making cross-lingual transfer similar to the monolingual cross-domain and semi-supervised settings. Thus self-training, which is effective for these settings, could be possibly beneficial to cross-lingual as well. This paper presents the first comprehensive study for self-training in cross-lingual dependency parsing. Three instance selection strategies are investigated, where two of which are based on the baseline dependency parsing model, and the third one adopts an auxiliary cross-lingual POS tagging model as evidence. We conduct experiments on the universal dependencies for eleven languages. Results show that self-training can boost the dependency parsing performances on the target languages. In addition, the POS tagger assistant instance selection can achieve further improvements consistently. Detailed analysis is conducted to examine the potentiality of self-training in-depth.

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End to End Chinese Lexical Fusion Recognition with Sememe Knowledge
Yijiang Liu | Meishan Zhang | Donghong Ji
Proceedings of the 28th International Conference on Computational Linguistics

In this paper, we present Chinese lexical fusion recognition, a new task which could be regarded as one kind of coreference recognition. First, we introduce the task in detail, showing the relationship with coreference recognition and differences from the existing tasks. Second, we propose an end-to-end model for the task, handling mentions as well as coreference relationship jointly. The model exploits the state-of-the-art contextualized BERT representations as an encoder, and is further enhanced with the sememe knowledge from HowNet by graph attention networks. We manually annotate a benchmark dataset for the task and then conduct experiments on it. Results demonstrate that our final model is effective and competitive for the task. Detailed analysis is offered for comprehensively understanding the new task and our proposed model.

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HiTrans: A Transformer-Based Context- and Speaker-Sensitive Model for Emotion Detection in Conversations
Jingye Li | Donghong Ji | Fei Li | Meishan Zhang | Yijiang Liu
Proceedings of the 28th International Conference on Computational Linguistics

Emotion detection in conversations (EDC) is to detect the emotion for each utterance in conversations that have multiple speakers. Different from the traditional non-conversational emotion detection, the model for EDC should be context-sensitive (e.g., understanding the whole conversation rather than one utterance) and speaker-sensitive (e.g., understanding which utterance belongs to which speaker). In this paper, we propose a transformer-based context- and speaker-sensitive model for EDC, namely HiTrans, which consists of two hierarchical transformers. We utilize BERT as the low-level transformer to generate local utterance representations, and feed them into another high-level transformer so that utterance representations could be sensitive to the global context of the conversation. Moreover, we exploit an auxiliary task to make our model speaker-sensitive, called pairwise utterance speaker verification (PUSV), which aims to classify whether two utterances belong to the same speaker. We evaluate our model on three benchmark datasets, namely EmoryNLP, MELD and IEMOCAP. Results show that our model outperforms previous state-of-the-art models.

2019

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Cross-Lingual Dependency Parsing Using Code-Mixed TreeBank
Meishan Zhang | Yue Zhang | Guohong Fu
Proceedings of the 2019 Conference on Empirical Methods in Natural Language Processing and the 9th International Joint Conference on Natural Language Processing (EMNLP-IJCNLP)

Treebank translation is a promising method for cross-lingual transfer of syntactic dependency knowledge. The basic idea is to map dependency arcs from a source treebank to its target translation according to word alignments. This method, however, can suffer from imperfect alignment between source and target words. To address this problem, we investigate syntactic transfer by code mixing, translating only confident words in a source treebank. Cross-lingual word embeddings are leveraged for transferring syntactic knowledge to the target from the resulting code-mixed treebank. Experiments on University Dependency Treebanks show that code-mixed treebanks are more effective than translated treebanks, giving highly competitive performances among cross-lingual parsing methods.

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Enhancing Opinion Role Labeling with Semantic-Aware Word Representations from Semantic Role Labeling
Meishan Zhang | Peili Liang | Guohong Fu
Proceedings of the 2019 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long and Short Papers)

Opinion role labeling (ORL) is an important task for fine-grained opinion mining, which identifies important opinion arguments such as holder and target for a given opinion trigger. The task is highly correlative with semantic role labeling (SRL), which identifies important semantic arguments such as agent and patient for a given predicate. As predicate agents and patients usually correspond to opinion holders and targets respectively, SRL could be valuable for ORL. In this work, we propose a simple and novel method to enhance ORL by utilizing SRL, presenting semantic-aware word representations which are learned from SRL. The representations are then fed into a baseline neural ORL model as basic inputs. We verify the proposed method on a benchmark MPQA corpus. Experimental results show that the proposed method is highly effective. In addition, we compare the method with two representative methods of SRL integration as well, finding that our method can outperform the two methods significantly, achieving 1.47% higher F-scores than the better one.

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Syntax-Enhanced Neural Machine Translation with Syntax-Aware Word Representations
Meishan Zhang | Zhenghua Li | Guohong Fu | Min Zhang
Proceedings of the 2019 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long and Short Papers)

Syntax has been demonstrated highly effective in neural machine translation (NMT). Previous NMT models integrate syntax by representing 1-best tree outputs from a well-trained parsing system, e.g., the representative Tree-RNN and Tree-Linearization methods, which may suffer from error propagation. In this work, we propose a novel method to integrate source-side syntax implicitly for NMT. The basic idea is to use the intermediate hidden representations of a well-trained end-to-end dependency parser, which are referred to as syntax-aware word representations (SAWRs). Then, we simply concatenate such SAWRs with ordinary word embeddings to enhance basic NMT models. The method can be straightforwardly integrated into the widely-used sequence-to-sequence (Seq2Seq) NMT models. We start with a representative RNN-based Seq2Seq baseline system, and test the effectiveness of our proposed method on two benchmark datasets of the Chinese-English and English-Vietnamese translation tasks, respectively. Experimental results show that the proposed approach is able to bring significant BLEU score improvements on the two datasets compared with the baseline, 1.74 points for Chinese-English translation and 0.80 point for English-Vietnamese translation, respectively. In addition, the approach also outperforms the explicit Tree-RNN and Tree-Linearization methods.

2018

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Transition-based Neural RST Parsing with Implicit Syntax Features
Nan Yu | Meishan Zhang | Guohong Fu
Proceedings of the 27th International Conference on Computational Linguistics

Syntax has been a useful source of information for statistical RST discourse parsing. Under the neural setting, a common approach integrates syntax by a recursive neural network (RNN), requiring discrete output trees produced by a supervised syntax parser. In this paper, we propose an implicit syntax feature extraction approach, using hidden-layer vectors extracted from a neural syntax parser. In addition, we propose a simple transition-based model as the baseline, further enhancing it with dynamic oracle. Experiments on the standard dataset show that our baseline model with dynamic oracle is highly competitive. When implicit syntax features are integrated, we are able to obtain further improvements, better than using explicit Tree-RNN.

2017

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End-to-End Neural Relation Extraction with Global Optimization
Meishan Zhang | Yue Zhang | Guohong Fu
Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing

Neural networks have shown promising results for relation extraction. State-of-the-art models cast the task as an end-to-end problem, solved incrementally using a local classifier. Yet previous work using statistical models have demonstrated that global optimization can achieve better performances compared to local classification. We build a globally optimized neural model for end-to-end relation extraction, proposing novel LSTM features in order to better learn context representations. In addition, we present a novel method to integrate syntactic information to facilitate global learning, yet requiring little background on syntactic grammars thus being easy to extend. Experimental results show that our proposed model is highly effective, achieving the best performances on two standard benchmarks.

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Transition-Based Disfluency Detection using LSTMs
Shaolei Wang | Wanxiang Che | Yue Zhang | Meishan Zhang | Ting Liu
Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing

In this paper, we model the problem of disfluency detection using a transition-based framework, which incrementally constructs and labels the disfluency chunk of input sentences using a new transition system without syntax information. Compared with sequence labeling methods, it can capture non-local chunk-level features; compared with joint parsing and disfluency detection methods, it is free for noise in syntax. Experiments show that our model achieves state-of-the-art f-score of 87.5% on the commonly used English Switchboard test set, and a set of in-house annotated Chinese data.

2016

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LibN3L:A Lightweight Package for Neural NLP
Meishan Zhang | Jie Yang | Zhiyang Teng | Yue Zhang
Proceedings of the Tenth International Conference on Language Resources and Evaluation (LREC'16)

We present a light-weight machine learning tool for NLP research. The package supports operations on both discrete and dense vectors, facilitating implementation of linear models as well as neural models. It provides several basic layers which mainly aims for single-layer linear and non-linear transformations. By using these layers, we can conveniently implement linear models and simple neural models. Besides, this package also integrates several complex layers by composing those basic layers, such as RNN, Attention Pooling, LSTM and gated RNN. Those complex layers can be used to implement deep neural models directly.

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Tweet Sarcasm Detection Using Deep Neural Network
Meishan Zhang | Yue Zhang | Guohong Fu
Proceedings of COLING 2016, the 26th International Conference on Computational Linguistics: Technical Papers

Sarcasm detection has been modeled as a binary document classification task, with rich features being defined manually over input documents. Traditional models employ discrete manual features to address the task, with much research effect being devoted to the design of effective feature templates. We investigate the use of neural network for tweet sarcasm detection, and compare the effects of the continuous automatic features with discrete manual features. In particular, we use a bi-directional gated recurrent neural network to capture syntactic and semantic information over tweets locally, and a pooling neural network to extract contextual features automatically from history tweets. Results show that neural features give improved accuracies for sarcasm detection, with different error distributions compared with discrete manual features.

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Transition-Based Neural Word Segmentation
Meishan Zhang | Yue Zhang | Guohong Fu
Proceedings of the 54th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

2015

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Neural Networks for Open Domain Targeted Sentiment
Meishan Zhang | Yue Zhang | Duy-Tin Vo
Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing

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Combining Discrete and Continuous Features for Deterministic Transition-based Dependency Parsing
Meishan Zhang | Yue Zhang
Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing

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A Transition-based Model for Joint Segmentation, POS-tagging and Normalization
Tao Qian | Yue Zhang | Meishan Zhang | Yafeng Ren | Donghong Ji
Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing

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Event-Driven Headline Generation
Rui Sun | Yue Zhang | Meishan Zhang | Donghong Ji
Proceedings of the 53rd Annual Meeting of the Association for Computational Linguistics and the 7th International Joint Conference on Natural Language Processing (Volume 1: Long Papers)

2014

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Character-Level Chinese Dependency Parsing
Meishan Zhang | Yue Zhang | Wanxiang Che | Ting Liu
Proceedings of the 52nd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

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Syntactic Processing Using Global Discriminative Learning and Beam-Search Decoding
Yue Zhang | Meishan Zhang | Ting Liu
Proceedings of the 52nd Annual Meeting of the Association for Computational Linguistics: Tutorials

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Type-Supervised Domain Adaptation for Joint Segmentation and POS-Tagging
Meishan Zhang | Yue Zhang | Wanxiang Che | Ting Liu
Proceedings of the 14th Conference of the European Chapter of the Association for Computational Linguistics

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Jointly or Separately: Which is Better for Parsing Heterogeneous Dependencies?
Meishan Zhang | Wanxiang Che | Yanqiu Shao | Ting Liu
Proceedings of COLING 2014, the 25th International Conference on Computational Linguistics: Technical Papers

2013

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Chinese Parsing Exploiting Characters
Meishan Zhang | Yue Zhang | Wanxiang Che | Ting Liu
Proceedings of the 51st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

2012

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SemEval-2012 Task 5: Chinese Semantic Dependency Parsing
Wanxiang Che | Meishan Zhang | Yanqiu Shao | Ting Liu
*SEM 2012: The First Joint Conference on Lexical and Computational Semantics – Volume 1: Proceedings of the main conference and the shared task, and Volume 2: Proceedings of the Sixth International Workshop on Semantic Evaluation (SemEval 2012)

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Micro blogs Oriented Word Segmentation System
Yijia Liu | Meishan Zhang | Wanxiang Che | Ting Liu | Yihe Deng
Proceedings of the Second CIPS-SIGHAN Joint Conference on Chinese Language Processing

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Multiple TreeBanks Integration for Chinese Phrase Structure Grammar Parsing Using Bagging
Meishan Zhang | Wanxiang Che | Ting Liu
Proceedings of the Second CIPS-SIGHAN Joint Conference on Chinese Language Processing

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Stacking Heterogeneous Joint Models of Chinese POS Tagging and Dependency Parsing
Meishan Zhang | Wanxiang Che | Ting Liu | Zhenghua Li
Proceedings of COLING 2012