Jintao Liu


2023

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Guide the Many-to-One Assignment: Open Information Extraction via IoU-aware Optimal Transport
Kaiwen Wei | Yiran Yang | Li Jin | Xian Sun | Zequn Zhang | Jingyuan Zhang | Xiao Li | Linhao Zhang | Jintao Liu | Guo Zhi
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

Open Information Extraction (OIE) seeks to extract structured information from raw text without the limitations of close ontology. Recently, the detection-based OIE methods have received great attention from the community due to their parallelism. However, as the essential step of those models, how to assign ground truth labels to the parallelly generated tuple proposals remains under-exploited. The commonly utilized Hungarian algorithm for this procedure is restricted to handling one-to-one assignment among the desired tuples and tuple proposals, which ignores the correlation between proposals and affects the recall of the models. To solve this problem, we propose a dynamic many-to-one label assignment strategy named IOT. Concretely, the label assignment process in OIE is formulated as an Optimal Transport (OT) problem. We leverage the intersection-over-union (IoU) as the assignment quality measurement, and convert the problem of finding the best assignment solution to the one of solving the optimal transport plan by maximizing the IoU values. To further utilize the knowledge from the assignment, we design an Assignment-guided Multi-granularity loss (AM) by simultaneously considering word-level and tuple-level information. Experiment results show the proposed method outperforms the state-of-the-art models on three benchmarks.

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Event Causality Extraction via Implicit Cause-Effect Interactions
Jintao Liu | Zequn Zhang | Kaiwen Wei | Zhi Guo | Xian Sun | Li Jin | Xiaoyu Li
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing

Event Causality Extraction (ECE) aims to extract the cause-effect event pairs from the given text, which requires the model to possess a strong reasoning ability to capture event causalities. However, existing works have not adequately exploited the interactions between the cause and effect event that could provide crucial clues for causality reasoning. To this end, we propose an Implicit Cause-Effect interaction (ICE) framework, which formulates ECE as a template-based conditional generation problem. The proposed method captures the implicit intra- and inter-event interactions by incorporating the privileged information (ground truth event types and arguments) for reasoning, and a knowledge distillation mechanism is introduced to alleviate the unavailability of privileged information in the test stage. Furthermore, to facilitate knowledge transfer from teacher to student, we design an event-level alignment strategy named Cause-Effect Optimal Transport (CEOT) to strengthen the semantic interactions of cause-effect event types and arguments. Experimental results indicate that ICE achieves state-of-the-art performance on the ECE-CCKS dataset.

2019

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Transformer-Based Capsule Network For Stock Movement Prediction
Jintao Liu | Hongfei Lin | Xikai Liu | Bo Xu | Yuqi Ren | Yufeng Diao | Liang Yang
Proceedings of the First Workshop on Financial Technology and Natural Language Processing