Patrick Nguyen


2018

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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.

2009

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Multi-scale Personalization for Voice Search Applications
Daniel Bolaños | Geoffrey Zweig | Patrick Nguyen
Proceedings of Human Language Technologies: The 2009 Annual Conference of the North American Chapter of the Association for Computational Linguistics, Companion Volume: Short Papers

2008

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Learning N-Best Correction Models from Implicit User Feedback in a Multi-Modal Local Search Application
Dan Bohus | Xiao Li | Patrick Nguyen | Geoffrey Zweig
Proceedings of the 9th SIGdial Workshop on Discourse and Dialogue

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Optimal Dialog in Consumer-Rating Systems using POMDP Framework
Zhifei Li | Patrick Nguyen | Geoffrey Zweig
Proceedings of the 9th SIGdial Workshop on Discourse and Dialogue

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Indirect-HMM-based Hypothesis Alignment for Combining Outputs from Machine Translation Systems
Xiaodong He | Mei Yang | Jianfeng Gao | Patrick Nguyen | Robert Moore
Proceedings of the 2008 Conference on Empirical Methods in Natural Language Processing

2007

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Voice-Rate: A Dialog System for Consumer Ratings
Geoffrey Zweig | Y.C. Ju | Patrick Nguyen | Dong Yu | Ye-Yi Wang | Alex Acero
Proceedings of Human Language Technologies: The Annual Conference of the North American Chapter of the Association for Computational Linguistics (NAACL-HLT)

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Training Non-Parametric Features for Statistical Machine Translation
Patrick Nguyen | Milind Mahajan | Xiaodong He
Proceedings of the Second Workshop on Statistical Machine Translation