Yonghui Wu


2024

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UF-HOBI at “Discharge Me!”: A Hybrid Solution for Discharge Summary Generation Through Prompt-based Tuning of GatorTronGPT Models
Mengxian Lyu | Cheng Peng | Daniel Paredes | Ziyi Chen | Aokun Chen | Jiang Bian | Yonghui Wu
Proceedings of the 23rd Workshop on Biomedical Natural Language Processing

Automatic generation of discharge summaries presents significant challenges due to the length of clinical documentation, the dispersed nature of patient information, and the diverse terminology used in healthcare. This paper presents a hybrid solution for generating discharge summary sections as part of our participation in the “Discharge Me!” Challenge at the BioNLP 2024 Shared Task. We developed a two-stage generation method using both extractive and abstractive techniques, in which we first apply name entity recognition (NER) to extract key clinical concepts, which are then used as input for a prompt-tuning based GatorTronGPT model to generate coherent text for two important sections including “Brief Hospital Course” and “Discharge Instructions”. Our system was ranked 5th in this challenge, achieving an overall score of 0.284. The results demonstrate the effectiveness of our hybrid solution in improving the quality of automated discharge section generation.

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Comprehensive Study on German Language Models for Clinical and Biomedical Text Understanding
Ahmad Idrissi-Yaghir | Amin Dada | Henning Schäfer | Kamyar Arzideh | Giulia Baldini | Jan Trienes | Max Hasin | Jeanette Bewersdorff | Cynthia S. Schmidt | Marie Bauer | Kaleb E. Smith | Jiang Bian | Yonghui Wu | Jörg Schlötterer | Torsten Zesch | Peter A. Horn | Christin Seifert | Felix Nensa | Jens Kleesiek | Christoph M. Friedrich
Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024)

Recent advances in natural language processing (NLP) can be largely attributed to the advent of pre-trained language models such as BERT and RoBERTa. While these models demonstrate remarkable performance on general datasets, they can struggle in specialized domains such as medicine, where unique domain-specific terminologies, domain-specific abbreviations, and varying document structures are common. This paper explores strategies for adapting these models to domain-specific requirements, primarily through continuous pre-training on domain-specific data. We pre-trained several German medical language models on 2.4B tokens derived from translated public English medical data and 3B tokens of German clinical data. The resulting models were evaluated on various German downstream tasks, including named entity recognition (NER), multi-label classification, and extractive question answering. Our results suggest that models augmented by clinical and translation-based pre-training typically outperform general domain models in medical contexts. We conclude that continuous pre-training has demonstrated the ability to match or even exceed the performance of clinical models trained from scratch. Furthermore, pre-training on clinical data or leveraging translated texts have proven to be reliable methods for domain adaptation in medical NLP tasks.

2023

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On the Impact of Cross-Domain Data on German Language Models
Amin Dada | Aokun Chen | Cheng Peng | Kaleb Smith | Ahmad Idrissi-Yaghir | Constantin Seibold | Jianning Li | Lars Heiliger | Christoph Friedrich | Daniel Truhn | Jan Egger | Jiang Bian | Jens Kleesiek | Yonghui Wu
Findings of the Association for Computational Linguistics: EMNLP 2023

Traditionally, large language models have been either trained on general web crawls or domain-specific data. However, recent successes of generative large language models, have shed light on the benefits of cross-domain datasets. To examine the significance of prioritizing data diversity over quality, we present a German dataset comprising texts from five domains, along with another dataset aimed at containing high-quality data. Through training a series of models ranging between 122M and 750M parameters on both datasets, we conduct a comprehensive benchmark on multiple downstream tasks. Our findings demonstrate that the models trained on the cross-domain dataset outperform those trained on quality data alone, leading to improvements up to 4.45% over the previous state-of-the-art.

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AnyTOD: A Programmable Task-Oriented Dialog System
Jeffrey Zhao | Yuan Cao | Raghav Gupta | Harrison Lee | Abhinav Rastogi | Mingqiu Wang | Hagen Soltau | Izhak Shafran | Yonghui Wu
Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing

We propose AnyTOD, an end-to-end, zero-shot task-oriented dialog (TOD) system capable of zero-shot adaptation onto unseen tasks or domains. We view TOD as a program executed by a language model (LM), where program logic and ontology is provided by a designer as a schema. To enable generalization to unseen schemas and programs without prior training, AnyTOD adopts a neuro-symbolic approach. A neural LM keeps track of events that occur during a conversation, and a symbolic program implementing dialog policy is executed to recommend actions AnyTOD should take. This approach drastically reduces data annotation and model training requirements, addressing the enduring challenge of rapidly adapting a TOD system to unseen tasks and domains. We demonstrate state-of-the-art results on STAR, ABCD and SGD benchmarks. We also demonstrate strong zero-shot transfer ability in low-resource settings, such as zero-shot transfer onto MultiWOZ. In addition, we release STARv2, an updated version of the STAR dataset with richer annotations, for benchmarking zero-shot task transfer for end-to-end TOD models.

2022

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Show, Don’t Tell: Demonstrations Outperform Descriptions for Schema-Guided Task-Oriented Dialogue
Raghav Gupta | Harrison Lee | Jeffrey Zhao | Yuan Cao | Abhinav Rastogi | Yonghui Wu
Proceedings of the 2022 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies

Building universal dialogue systems that operate across multiple domains/APIs and generalize to new ones with minimal overhead is a critical challenge. Recent works have leveraged natural language descriptions of schema elements to enable such systems; however, descriptions only indirectly convey schema semantics. In this work, we propose Show, Don’t Tell, which prompts seq2seq models with a labeled example dialogue to show the semantics of schema elements rather than tell the model through descriptions. While requiring similar effort from service developers as generating descriptions, we show that using short examples as schema representations with large language models results in state-of-the-art performance on two popular dialogue state tracking benchmarks designed to measure zero-shot generalization - the Schema-Guided Dialogue dataset and the MultiWOZ leave-one-out benchmark.

2021

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Effective Sequence-to-Sequence Dialogue State Tracking
Jeffrey Zhao | Mahdis Mahdieh | Ye Zhang | Yuan Cao | Yonghui Wu
Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing

Sequence-to-sequence models have been applied to a wide variety of NLP tasks, but how to properly use them for dialogue state tracking has not been systematically investigated. In this paper, we study this problem from the perspectives of pre-training objectives as well as the formats of context representations. We demonstrate that the choice of pre-training objective makes a significant difference to the state tracking quality. In particular, we find that masked span prediction is more effective than auto-regressive language modeling. We also explore using Pegasus, a span prediction-based pre-training objective for text summarization, for the state tracking model. We found that pre-training for the seemingly distant summarization task works surprisingly well for dialogue state tracking. In addition, we found that while recurrent state context representation works also reasonably well, the model may have a hard time recovering from earlier mistakes. We conducted experiments on the MultiWOZ 2.1-2.4, WOZ 2.0, and DSTC2 datasets with consistent observations.

2020

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Leveraging Monolingual Data with Self-Supervision for Multilingual Neural Machine Translation
Aditya Siddhant | Ankur Bapna | Yuan Cao | Orhan Firat | Mia Chen | Sneha Kudugunta | Naveen Arivazhagan | Yonghui Wu
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics

Over the last few years two promising research directions in low-resource neural machine translation (NMT) have emerged. The first focuses on utilizing high-resource languages to improve the quality of low-resource languages via multilingual NMT. The second direction employs monolingual data with self-supervision to pre-train translation models, followed by fine-tuning on small amounts of supervised data. In this work, we join these two lines of research and demonstrate the efficacy of monolingual data with self-supervision in multilingual NMT. We offer three major results: (i) Using monolingual data significantly boosts the translation quality of low-resource languages in multilingual models. (ii) Self-supervision improves zero-shot translation quality in multilingual models. (iii) Leveraging monolingual data with self-supervision provides a viable path towards adding new languages to multilingual models, getting up to 33 BLEU on ro-en translation without any parallel data or back-translation.

2018

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The Best of Both Worlds: Combining Recent Advances in Neural Machine Translation
Mia Xu Chen | Orhan Firat | Ankur Bapna | Melvin Johnson | Wolfgang Macherey | George Foster | Llion Jones | Mike Schuster | Noam Shazeer | Niki Parmar | Ashish Vaswani | Jakob Uszkoreit | Lukasz Kaiser | Zhifeng Chen | Yonghui Wu | Macduff Hughes
Proceedings of the 56th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

The past year has witnessed rapid advances in sequence-to-sequence (seq2seq) modeling for Machine Translation (MT). The classic RNN-based approaches to MT were first out-performed by the convolutional seq2seq model, which was then out-performed by the more recent Transformer model. Each of these new approaches consists of a fundamental architecture accompanied by a set of modeling and training techniques that are in principle applicable to other seq2seq architectures. In this paper, we tease apart the new architectures and their accompanying techniques in two ways. First, we identify several key modeling and training techniques, and apply them to the RNN architecture, yielding a new RNMT+ model that outperforms all of the three fundamental architectures on the benchmark WMT’14 English to French and English to German tasks. Second, we analyze the properties of each fundamental seq2seq architecture and devise new hybrid architectures intended to combine their strengths. Our hybrid models obtain further improvements, outperforming the RNMT+ model on both benchmark datasets.

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Training Deeper Neural Machine Translation Models with Transparent Attention
Ankur Bapna | Mia Chen | Orhan Firat | Yuan Cao | Yonghui Wu
Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing

While current state-of-the-art NMT models, such as RNN seq2seq and Transformers, possess a large number of parameters, they are still shallow in comparison to convolutional models used for both text and vision applications. In this work we attempt to train significantly (2-3x) deeper Transformer and Bi-RNN encoders for machine translation. We propose a simple modification to the attention mechanism that eases the optimization of deeper models, and results in consistent gains of 0.7-1.1 BLEU on the benchmark WMT’14 English-German and WMT’15 Czech-English tasks for both architectures.

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CaLcs: Continuously Approximating Longest Common Subsequence for Sequence Level Optimization
Semih Yavuz | Chung-Cheng Chiu | Patrick Nguyen | Yonghui Wu
Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing

Maximum-likelihood estimation (MLE) is one of the most widely used approaches for training structured prediction models for text-generation based natural language processing applications. However, besides exposure bias, models trained with MLE suffer from wrong objective problem where they are trained to maximize the word-level correct next step prediction, but are evaluated with respect to sequence-level discrete metrics such as ROUGE and BLEU. Several variants of policy-gradient methods address some of these problems by optimizing for final discrete evaluation metrics and showing improvements over MLE training for downstream tasks like text summarization and machine translation. However, policy-gradient methods suffers from high sample variance, making the training process very difficult and unstable. In this paper, we present an alternative direction towards mitigating this problem by introducing a new objective (CaLcs) based on a differentiable surrogate of longest common subsequence (LCS) measure that captures sequence-level structure similarity. Experimental results on abstractive summarization and machine translation validate the effectiveness of the proposed approach.

2017

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Google’s Multilingual Neural Machine Translation System: Enabling Zero-Shot Translation
Melvin Johnson | Mike Schuster | Quoc V. Le | Maxim Krikun | Yonghui Wu | Zhifeng Chen | Nikhil Thorat | Fernanda Viégas | Martin Wattenberg | Greg Corrado | Macduff Hughes | Jeffrey Dean
Transactions of the Association for Computational Linguistics, Volume 5

We propose a simple solution to use a single Neural Machine Translation (NMT) model to translate between multiple languages. Our solution requires no changes to the model architecture from a standard NMT system but instead introduces an artificial token at the beginning of the input sentence to specify the required target language. Using a shared wordpiece vocabulary, our approach enables Multilingual NMT systems using a single model. On the WMT’14 benchmarks, a single multilingual model achieves comparable performance for English→French and surpasses state-of-theart results for English→German. Similarly, a single multilingual model surpasses state-of-the-art results for French→English and German→English on WMT’14 and WMT’15 benchmarks, respectively. On production corpora, multilingual models of up to twelve language pairs allow for better translation of many individual pairs. Our models can also learn to perform implicit bridging between language pairs never seen explicitly during training, showing that transfer learning and zero-shot translation is possible for neural translation. Finally, we show analyses that hints at a universal interlingua representation in our models and also show some interesting examples when mixing languages.

2016

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UTHealth at SemEval-2016 Task 12: an End-to-End System for Temporal Information Extraction from Clinical Notes
Hee-Jin Lee | Hua Xu | Jingqi Wang | Yaoyun Zhang | Sungrim Moon | Jun Xu | Yonghui Wu
Proceedings of the 10th International Workshop on Semantic Evaluation (SemEval-2016)

2015

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UTH-CCB: The Participation of the SemEval 2015 Challenge – Task 14
Jun Xu | Yaoyun Zhang | Jingqi Wang | Yonghui Wu | Min Jiang | Ergin Soysal | Hua Xu
Proceedings of the 9th International Workshop on Semantic Evaluation (SemEval 2015)

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Clinical Abbreviation Disambiguation Using Neural Word Embeddings
Yonghui Wu | Jun Xu | Yaoyun Zhang | Hua Xu
Proceedings of BioNLP 15

2014

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UTH_CCB: A report for SemEval 2014 – Task 7 Analysis of Clinical Text
Yaoyun Zhang | Jingqi Wang | Buzhou Tang | Yonghui Wu | Min Jiang | Yukun Chen | Hua Xu
Proceedings of the 8th International Workshop on Semantic Evaluation (SemEval 2014)