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From unified phrase representation to bilingual phrase alignment in an unsupervised manner

Published online by Cambridge University Press:  01 August 2022

Jingshu Liu ,
Emmanuel Morin ,
Sebastian Peña Saldarriaga  and
Joseph Lark
Jingshu Liu*
Affiliation:
LS2N – UMR CNRS 6004, Université de Nantes, Nantes, France Dictanova, 6 rue René Viviani, 44200 Nantes, France
Emmanuel Morin
Affiliation:
LS2N – UMR CNRS 6004, Université de Nantes, Nantes, France Dictanova, 6 rue René Viviani, 44200 Nantes, France
Sebastian Peña Saldarriaga
Affiliation:
Dictanova, 6 rue René Viviani, 44200 Nantes, France
Joseph Lark
Affiliation:
Dictanova, 6 rue René Viviani, 44200 Nantes, France
*
*Corresponding author. E-mail: liujish931@hotmail.com
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Abstract

Significant advances have been achieved in bilingual word-level alignment, yet the challenge remains for phrase-level alignment. Moreover, the need for parallel data is a critical drawback for the alignment task. This work proposes a system that alleviates these two problems: a unified phrase representation model using cross-lingual word embeddings as input and an unsupervised training algorithm inspired by recent works on neural machine translation. The system consists of a sequence-to-sequence architecture where a short sequence encoder constructs cross-lingual representations of phrases of any length, then an LSTM network decodes them w.r.t their contexts. After training with comparable corpora and existing key phrase extraction, our encoder provides cross-lingual phrase representations that can be compared without further transformation. Experiments on five data sets show that our method obtains state-of-the-art results on the bilingual phrase alignment task and improves the results of different length phrase alignment by a mean of 8.8 points in MAP.

Keywords

MultilingualityPhrase representationBilingual alignmentWord semantics
Type
Article
Information
Natural Language Engineering , Volume 29 , Issue 3 , May 2023 , pp. 643 - 668
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Copyright
© The Author(s), 2022. Published by Cambridge University Press

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