Machine Translation without Word Alignments
While the vast majority of statistical machine translation systems maintain an alignment of source and target words (or word groups), some work explored machine translation without such alignment.
MT Without Word Alignment is the main subject of 5 publications. 4 are discussed here.
Publications
While word alignment is generally assumed to be an essential element of statistical translation models, methods have been proposed that first generate a bag of words from the source bag of words and then apply an ordering model
Venkatapathy, Sriram and Bangalore, Srinivas (2007):
Three models for discriminative machine translation using Global Lexical Selection and Sentence Reconstruction, Proceedings of SSST, NAACL-HLT 2007 / AMTA Workshop on Syntax and Structure in Statistical Translation
@InProceedings{venkatapathy-bangalore:2007:SSST,
author = {Venkatapathy, Sriram and Bangalore, Srinivas},
title = {Three models for discriminative machine translation using Global Lexical Selection and Sentence Reconstruction},
booktitle = {Proceedings of SSST, NAACL-HLT 2007 / AMTA Workshop on Syntax and Structure in Statistical Translation},
month = {April},
address = {Rochester, New York},
publisher = {Association for Computational Linguistics},
pages = {96--102},
url = {
http://www.aclweb.org/anthology/W/W07/W07-0413},
year = 2007
}
(Venkatapathy and Bangalore, 2007;
Bangalore, Srinivas and Haffner, Patrick and Kanthak, Stephan (2007):
Statistical Machine Translation through Global Lexical Selection and Sentence Reconstruction, Proceedings of the 45th Annual Meeting of the Association of Computational Linguistics
@InProceedings{bangalore-haffner-kanthak:2007:ACLMain,
author = {Bangalore, Srinivas and Haffner, Patrick and Kanthak, Stephan},
title = {Statistical Machine Translation through Global Lexical Selection and Sentence Reconstruction},
booktitle = {Proceedings of the 45th Annual Meeting of the Association of Computational Linguistics},
month = {June},
address = {Prague, Czech Republic},
publisher = {Association for Computational Linguistics},
pages = {152--159},
url = {
http://www.aclweb.org/anthology/P/P07/P07-1020},
year = 2007
}
Bangalore et al., 2007).
Alignment-free word translation models may be used as a feature function in traditional models.
Mauser, Arne and Hasan, Saša and Ney, Hermann (2009):
Extending Statistical Machine Translation with Discriminative and Trigger-Based Lexicon Models, Proceedings of the 2009 Conference on Empirical Methods in Natural Language Processing
@InProceedings{mauser-hasan-ney:2009:EMNLP,
author = {Mauser, Arne and Hasan, Sa{\v{s}}a and Ney, Hermann},
title = {Extending Statistical Machine Translation with Discriminative and Trigger-Based Lexicon Models},
booktitle = {Proceedings of the 2009 Conference on Empirical Methods in Natural Language Processing},
month = {August},
address = {Singapore},
publisher = {Association for Computational Linguistics},
pages = {210--218},
url = {
http://www.aclweb.org/anthology/D/D09/D09-1022},
year = 2009
}
Mauser et al. (2009) employs a maximum entropy model that predicts output words from all source words as an additional scoring function.
Matthias Huck and David Vilar and Daniel Stein and Hermann Ney (2011):
Advancements in Arabic-to-English Hierarchical Machine Translation, Proceedings of the 15th International Conference of the European Association for Machine Translation (EAMT)
mentioned in Domain Adaptation and MT Without Word Alignment@inproceedings{eamt11:Huck,
author = {Matthias Huck and David Vilar and Daniel Stein and Hermann Ney},
title = {Advancements in {A}rabic-to-{E}nglish Hierarchical Machine Translation},
url = {
http://www-i6.informatik.rwth-aachen.de/publications/download/716/HuckMatthiasVilarDavidSteinDanielNeyHermann--AdvancementsinArabic-to-EnglishHierarchicalMachineTranslation--2011.pdf},
googlescholar = {72178570233796985},
pages = {273--289},
booktitle = {Proceedings of the 15th International Conference of the European Association for Machine Translation (EAMT)},
location = {Leuven, Belgium},
editor = {Mikel L. Forcada and Heidi Depraetere and Vincent Vandeghinste},
year = 2011
}
Huck et al. (2011) confirm the effectiveness of the method.
Benchmarks
Discussion
Related Topics
New Publications
Langlais, Phillippe (2013):
Mapping Source to Target Strings without Alignment by Analogical Learning: A Case Study with Transliteration, Proceedings of the 51st Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)
@InProceedings{langlais:2013:Short,
author = {Langlais, Phillippe},
title = {Mapping Source to Target Strings without Alignment by Analogical Learning: A Case Study with Transliteration},
booktitle = {Proceedings of the 51st Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)},
month = {August},
address = {Sofia, Bulgaria},
publisher = {Association for Computational Linguistics},
pages = {684--689},
url = {
http://www.aclweb.org/anthology/P13-2120},
year = 2013
}
Langlais (2013)