Refinements of Phrase Based Models
Phrase-based models have refined in many ways. We discuss in detail reordering models, pruning and smoothing methods, and the inclusion of context features in separate sections elsewhere, and address here other refinements.
Phrase Based Model Refinement is the main subject of 27 publications. 4 are discussed here.
Publications
Usually, the segmentation of the source is not modeled, or only a phrase count feature is used, but adding a source phrase segmentation model may be beneficial 
Blackwood, Graeme  and  de Gispert, Adrià  and  Byrne, William (2008): 
Phrasal Segmentation Models for Statistical Machine Translation, Coling 2008: Companion volume: Posters and Demonstrations 
 
 
 
@InProceedings{blackwood-degispert-byrne:2008:POSTERS,
author = {Blackwood, Graeme  and  de Gispert, Adri\`{a}  and  Byrne, William},
title = {Phrasal Segmentation Models for Statistical Machine Translation},
booktitle = {Coling 2008: Companion volume: Posters and Demonstrations},
month = {August},
address = {Manchester, UK},
publisher = {Coling 2008 Organizing Committee},
pages = {17--20},
url = {
http://www.aclweb.org/anthology/C08-3005},
year = 2008
}
 (Blackwood et al., 2008). When using automatically learned segmentation boundaries these may outperform linguistically motivated constituent boundaries 
Xiong, Deyi  and  Zhang, Min  and  Li, Haizhou (2010): 
Learning Translation Boundaries for Phrase-Based Decoding, Human Language Technologies: The 2010 Annual Conference of the North American Chapter of the Association for Computational Linguistics 
 
 
 
@InProceedings{xiong-zhang-li:2010:NAACLHLT,
author = {Xiong, Deyi  and  Zhang, Min  and  Li, Haizhou},
title = {Learning Translation Boundaries for Phrase-Based Decoding},
booktitle = {Human Language Technologies: The 2010 Annual Conference of the North American Chapter of the Association for Computational Linguistics},
month = {June},
address = {Los Angeles, California},
publisher = {Association for Computational Linguistics},
pages = {136--144},
url = {
http://www.aclweb.org/anthology/N10-1016},
year = 2010
}
 (Xiong et al., 2010).
Models may allow word insertion to account for spurious function words 
Bo Xu (2005): 
Phrase-Based Statistical Machine Translation for MANOS System, Proceedings of the Tenth Machine Translation Summit (MT Summit X) 
 
 
@InProceedings{Xu:2005:MTS,
author = {Bo Xu},
title = {Phrase-Based Statistical Machine Translation for {MANOS} System},
booktitle = {Proceedings of the Tenth Machine Translation Summit (MT Summit X)},
month = {September},
address = {Phuket, Thailand},
year = 2005
}
 (Xu, 2005), or allow for words to be dropped by translating them into the empty phrase 
Li, Chi-Ho  and  Zhang, Hailei  and  Zhang, Dongdong  and  Li, Mu  and  Zhou, Ming (2008): 
An Empirical Study in Source Word Deletion for Phrase-Based Statistical Machine Translation, Proceedings of the Third Workshop on Statistical Machine Translation 
 
 
 
@InProceedings{li-EtAl:2008:WMT,
author = {Li, Chi-Ho  and  Zhang, Hailei  and  Zhang, Dongdong  and  Li, Mu  and  Zhou, Ming},
title = {An Empirical Study in Source Word Deletion for Phrase-Based Statistical Machine Translation},
booktitle = {Proceedings of the Third Workshop on Statistical Machine Translation},
month = {June},
address = {Columbus, Ohio},
publisher = {Association for Computational Linguistics},
pages = {1--8},
url = {
http://www.aclweb.org/anthology/W/W08/W08-0301},
year = 2008
}
 (Li et al., 2008).
Benchmarks
Discussion
Related Topics
New Publications
Nadir Durrani and Helmut Schmid and Alexander Fraser and Philipp Koehn and Hinrich Schütze (2015): 
The Operation Sequence Model -- Combining N-Gram-Based and Phrase-Based Statistical Machine Translation, Computational Linguistics 
 
 
@Article{Durrani:CL2015,
author = {Nadir Durrani and Helmut Schmid and Alexander Fraser and Philipp Koehn and Hinrich Sch{\"u}tze},
title = {The Operation Sequence Model -- Combining N-Gram-Based and Phrase-Based Statistical Machine Translation},
journal = {Computational Linguistics},
volume = {41},
number = {2},
month = {June},
year = 2015
}
 Durrani et al. (2015)
Kyaw Thu, Ye  and  Finch, Andrew  and  Sumita, Eiichiro (2016): 
Interlocking Phrases in Phrase-based Statistical Machine Translation, Proceedings of the 2016 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies 
 
 
 
@InProceedings{kyawthu-finch-sumita:2016:N16-1,
author = {Kyaw Thu, Ye  and  Finch, Andrew  and  Sumita, Eiichiro},
title = {Interlocking Phrases in Phrase-based Statistical Machine Translation},
booktitle = {Proceedings of the 2016 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies},
month = {June},
address = {San Diego, California},
publisher = {Association for Computational Linguistics},
pages = {1076--1081},
url = {
http://www.aclweb.org/anthology/N16-1124},
year = 2016
}
 Thu et al. (2016)
Matthias Huck and Erik Scharwächter and Hermann Ney (2013): 
Source-Side Discontinuous Phrases for Machine Translation: A Comparative Study on Phrase Extraction and Search, The Prague Bulletin of Mathematical Linguistics 
 
 
 
@article{pbml-99-huck-scharwaechter-ney,
author = {Matthias Huck and Erik Scharw{\"a}chter and Hermann Ney},
title = {Source-Side Discontinuous Phrases for Machine Translation: A Comparative Study on Phrase Extraction and Search},
url = {
http://ufal.mff.cuni.cz/pbml/99/art-huck-scharwaechter-ney.pdf},
pages = {17--38},
journal = {The Prague Bulletin of Mathematical Linguistics},
volume = {99},
year = 2013
}
 Huck et al. (2013)
Feng, Yang  and  Cohn, Trevor  and  Du, Xinkai (2014): 
Factored Markov Translation with Robust Modeling, Proceedings of the Eighteenth Conference on Computational Natural Language Learning 
 
 
 
@InProceedings{feng-cohn-du:2014:W14-16,
author = {Feng, Yang  and  Cohn, Trevor  and  Du, Xinkai},
title = {Factored Markov Translation with Robust Modeling},
booktitle = {Proceedings of the Eighteenth Conference on Computational Natural Language Learning},
month = {June},
address = {Ann Arbor, Michigan},
publisher = {Association for Computational Linguistics},
pages = {151--159},
url = {
http://www.aclweb.org/anthology/W14-1616},
year = 2014
}
 Feng et al. (2014)
Durrani, Nadir  and  Fraser, Alexander  and  Schmid, Helmut  and  Hoang, Hieu  and  Koehn, Philipp (2013): 
Can Markov Models Over Minimal Translation Units Help Phrase-Based SMT?, Proceedings of the 51st Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers) 
 
 
 
@InProceedings{durrani-EtAl:2013:Short,
author = {Durrani, Nadir  and  Fraser, Alexander  and  Schmid, Helmut  and  Hoang, Hieu  and  Koehn, Philipp},
title = {Can Markov Models Over Minimal Translation Units Help Phrase-Based SMT?},
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 = {399--405},
url = {
http://www.aclweb.org/anthology/P13-2071},
year = 2013
}
 Durrani et al. (2013)
Durrani, Nadir  and  Fraser, Alexander  and  Schmid, Helmut (2013): 
Model With Minimal Translation Units, But Decode With Phrases, Proceedings of the 2013 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies 
 
 
 
@InProceedings{durrani-fraser-schmid:2013:NAACL-HLT,
author = {Durrani, Nadir  and  Fraser, Alexander  and  Schmid, Helmut},
title = {Model With Minimal Translation Units, But Decode With Phrases},
booktitle = {Proceedings of the 2013 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies},
month = {June},
address = {Atlanta, Georgia},
publisher = {Association for Computational Linguistics},
pages = {1--11},
url = {
http://www.aclweb.org/anthology/N13-1001},
year = 2013
}
 Durrani et al. (2013)
Servan, Christophe  and  Petitrenaud, Simon (2012): 
Calculation of Phrase Probabilities for Statistical Machine Translation by using Belief Functions, Proceedings of COLING 2012: Posters 
 
 
 
@InProceedings{servan-petitrenaud:2012:POSTERS,
author = {Servan, Christophe  and  Petitrenaud, Simon},
title = {Calculation of Phrase Probabilities for Statistical Machine Translation by using Belief Functions},
booktitle = {Proceedings of COLING 2012: Posters},
month = {December},
address = {Mumbai, India},
publisher = {The COLING 2012 Organizing Committee},
pages = {1101--1110},
url = {
http://www.aclweb.org/anthology/C12-2107},
year = 2012
}
 Servan and Petitrenaud (2012)
Minwei Feng and Arne Mauser and Hermann Ney (2010): 
A Source-side Decoding Sequence Model for Statistical Machine Translation, Proceedings of the Ninth Conference of the Association for Machine Translation in the Americas 
 
 
 
@inproceedings{AMTA-2010-Feng,
author = {Minwei Feng and Arne Mauser and Hermann Ney},
title = {A Source-side Decoding Sequence Model for Statistical Machine Translation},
url = {
http://www.mt-archive.info/AMTA-2010-Feng.pdf},
booktitle = {Proceedings of the Ninth Conference of the Association for Machine Translation in the Americas},
location = {Denver, Colorado},
year = 2010
}
 Feng et al. (2010)
Huck, Matthias  and  Ney, Hermann (2012): 
Insertion and Deletion Models for Statistical Machine Translation, Proceedings of the 2012 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies 
 
 
 
@InProceedings{huck-ney:2012:NAACL-HLT,
author = {Huck, Matthias  and  Ney, Hermann},
title = {Insertion and Deletion Models for Statistical Machine Translation},
booktitle = {Proceedings of the 2012 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies},
month = {June},
address = {Montr\'{e}al, Canada},
publisher = {Association for Computational Linguistics},
pages = {347--351},
url = {
http://www.aclweb.org/anthology/N12-1035},
year = 2012
}
 Huck and Ney (2012)
Le, Hai-Son  and  Allauzen, Alexandre  and  Yvon, François (2012): 
Continuous Space Translation Models with Neural Networks, Proceedings of the 2012 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies 
 
 
 
 mentioned in Phrase Based Model Refinement and Neural Components In Statistical Machine Translation@InProceedings{le-allauzen-yvon:2012:NAACL-HLT,
author = {Le, Hai-Son  and  Allauzen, Alexandre  and  Yvon, Fran\c{c}ois},
title = {Continuous Space Translation Models with Neural Networks},
booktitle = {Proceedings of the 2012 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies},
month = {June},
address = {Montr\'{e}al, Canada},
publisher = {Association for Computational Linguistics},
pages = {39--48},
url = {
http://www.aclweb.org/anthology/N12-1005},
year = 2012
}
 Le et al. (2012)
Costa-jussà, Marta Ruiz and  Fonollosa, José A. R. (2005): 
Improving Phrase-Based Statistical Translation by Modifying Phrase Extraction and Including Several Features, Proceedings of the ACL Workshop on Building and Using Parallel Texts 
 
 
 
@InProceedings{ruizcostajussa-fonollosa:2005:WPT,
author = {Costa-juss\`a, Marta Ruiz and  Fonollosa, Jos\'e A. R.},
title = {Improving Phrase-Based Statistical Translation by Modifying Phrase Extraction and Including Several Features},
booktitle = {Proceedings of the ACL Workshop on Building and Using Parallel Texts},
month = {June},
address = {Ann Arbor, Michigan},
publisher = {Association for Computational Linguistics},
pages = {149--154},
url = {
http://www.aclweb.org/anthology/W/W05/W05-0827},
year = 2005
}
 Costa-jussà and Fonollosa (2005)
Durrani, Nadir  and  Schmid, Helmut  and  Fraser, Alexander (2011): 
A Joint Sequence Translation Model with Integrated Reordering, Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies 
 
 
 
@InProceedings{durrani-schmid-fraser:2011:ACL-HLT2011,
author = {Durrani, Nadir  and  Schmid, Helmut  and  Fraser, Alexander},
title = {A Joint Sequence Translation Model with Integrated Reordering},
booktitle = {Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies},
month = {June},
address = {Portland, Oregon, USA},
publisher = {Association for Computational Linguistics},
pages = {1045--1054},
url = {
http://www.aclweb.org/anthology/P11-1105},
year = 2011
}
 Durrani et al. (2011)
Saab Mansour and Hermann Ney (2012): 
A simple and effective weighted phrase extraction for machine translation adaptation, Proceedings of the seventh International Workshop on Spoken Language Translation (IWSLT) 
 
 
 
@inproceedings{iwslt12:Mansour,
author = {Saab Mansour and Hermann Ney},
title = {A simple and effective weighted phrase extraction for machine translation adaptation},
url = {
http://www.mt-archive.info/IWSLT-2012-Mansour.pdf},
pages = {193-200},
booktitle = {Proceedings of the seventh International Workshop on Spoken Language Translation (IWSLT)},
location = {Hong Kong},
year = 2012
}
 Mansour and Ney (2012)
Finch, Andrew  and  Sumita, Eiichiro (2009): 
Bidirectional Phrase-based Statistical Machine Translation, Proceedings of the 2009 Conference on Empirical Methods in Natural Language Processing 
 
 
 
@InProceedings{finch-sumita:2009:EMNLP,
author = {Finch, Andrew  and  Sumita, Eiichiro},
title = {Bidirectional Phrase-based Statistical Machine Translation},
booktitle = {Proceedings of the 2009 Conference on Empirical Methods in Natural Language Processing},
month = {August},
address = {Singapore},
publisher = {Association for Computational Linguistics},
pages = {1124--1132},
url = {
http://www.aclweb.org/anthology/D/D09/D09-1117},
year = 2009
}
 Finch and Sumita (2009)
Sirvan Yahyaei and Christof Monz (2009): 
Decoding by Dynamic Chunking for Statistical Machine Translation, Proceedings of the Twelfth Machine Translation Summit (MT Summit XII) 
 
 
 
@inproceedings{MTS09:Yahyaei,
author = {Sirvan Yahyaei and Christof Monz},
title = {Decoding by Dynamic Chunking for Statistical Machine Translation},
url = {
http://eprints.pascal-network.org/archive/00006713/01/mtsummit2009.pdf},
googlescholar = {6659763717595252555},
booktitle = {Proceedings of the Twelfth Machine Translation Summit (MT Summit XII)},
publisher = {International Association for Machine Translation},
location = {Ottawa, Ontario, Canada},
year = 2009
}
 Yahyaei and Monz (2009)
Liberato, Frank  and  Mohit, Behrang  and  Hwa, Rebecca (2010): 
Improving Phrase-Based Translation with Prototypes of Short Phrases, Human Language Technologies: The 2010 Annual Conference of the North American Chapter of the Association for Computational Linguistics 
 
 
 
@InProceedings{liberato-mohit-hwa:2010:NAACLHLT,
author = {Liberato, Frank  and  Mohit, Behrang  and  Hwa, Rebecca},
title = {Improving Phrase-Based Translation with Prototypes of Short Phrases},
booktitle = {Human Language Technologies: The 2010 Annual Conference of the North American Chapter of the Association for Computational Linguistics},
month = {June},
address = {Los Angeles, California},
publisher = {Association for Computational Linguistics},
pages = {301--304},
url = {
http://www.aclweb.org/anthology/N10-1040},
year = 2010
}
 Liberato et al. (2010)
Wang Ling and Tiago Luís and Joao Graça and Luísa Coheur and Isabel Trancoso (2010): 
Towards a General and Extensible Phrase-Extraction Algorithm, Proceedings of the seventh International Workshop on Spoken Language Translation (IWSLT) 
 
 
@inproceedings{iwslt10:TP:ling,
author = {Wang Ling and Tiago Lu\'{i}s and Joao Gra\c{c}a and Lu\'{i}sa Coheur and Isabel Trancoso},
title = {{Towards a General and Extensible Phrase-Extraction Algorithm}},
editor = {Marcello Federico and Ian Lane and Michael Paul and Fran\c{c}ois Yvon},
booktitle = {Proceedings of the seventh International Workshop on Spoken Language Translation (IWSLT)},
pages = {313--320},
location = {Paris, France},
year = 2010
}
 Ling et al. (2010)
Markus Saers and Dekai Wu (2011): 
Principled Induction of Phrasal Bilexica, Proceedings of the 15th International Conference of the European Association for Machine Translation (EAMT) 
 
 
 
@inproceedings{eamt11:Saers,
author = {Markus Saers and Dekai Wu},
title = {Principled Induction of Phrasal Bilexica},
url = {
http://mt-archive.info/EAMT-2011-Saers.pdf},
googlescholar = {14857983361834427223},
pages = {313--320},
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
}
 Saers and Wu (2011)
Zbib, Rabih  and  Matsoukas, Spyros  and  Schwartz, Richard  and  Makhoul, John (2010): 
Decision Trees for Lexical Smoothing in Statistical Machine Translation, Proceedings of the Joint Fifth Workshop on Statistical Machine Translation and MetricsMATR 
 
 
 
@InProceedings{zbib-EtAl:2010:WMT,
author = {Zbib, Rabih  and  Matsoukas, Spyros  and  Schwartz, Richard  and  Makhoul, John},
title = {Decision Trees for Lexical Smoothing in Statistical Machine Translation},
booktitle = {Proceedings of the Joint Fifth Workshop on Statistical Machine Translation and MetricsMATR},
month = {July},
address = {Uppsala, Sweden},
publisher = {Association for Computational Linguistics},
pages = {428--437},
url = {
http://www.aclweb.org/anthology/W10-1763},
year = 2010
}
 Zbib et al. (2010)
Cao, Hailong  and  Finch, Andrew  and  Sumita, Eiichiro (2010): 
Syntactic Constraints on Phrase Extraction for Phrase-Based Machine Translation, Proceedings of the 4th Workshop on Syntax and Structure in Statistical Translation 
 
 
 
@InProceedings{cao-finch-sumita:2010:SSST,
author = {Cao, Hailong  and  Finch, Andrew  and  Sumita, Eiichiro},
title = {Syntactic Constraints on Phrase Extraction for Phrase-Based Machine Translation},
booktitle = {Proceedings of the 4th Workshop on Syntax and Structure in Statistical Translation},
month = {August},
address = {Beijing, China},
publisher = {Coling 2010 Organizing Committee},
pages = {28--33},
url = {
http://www.aclweb.org/anthology/W10-3804},
year = 2010
}
 Cao et al. (2010)
Lavergne, Thomas  and  Allauzen, Alexandre  and  Crego, Josep Maria  and  Yvon, François (2011): 
From n-gram-based to CRF-based Translation Models, Proceedings of the Sixth Workshop on Statistical Machine Translation 
 
 
 
@InProceedings{lavergne-EtAl:2011:WMT,
author = {Lavergne, Thomas  and  Allauzen, Alexandre  and  Crego, Josep Maria  and  Yvon, Fran\c{c}ois},
title = {From n-gram-based to CRF-based Translation Models},
booktitle = {Proceedings of the Sixth Workshop on Statistical Machine Translation},
month = {July},
address = {Edinburgh, Scotland},
publisher = {Association for Computational Linguistics},
pages = {542--553},
url = {
http://www.aclweb.org/anthology/W11-2168},
year = 2011
}
 Lavergne et al. (2011)
Costa-jussà, Marta Ruiz and  Crego, Josep M.  and  Lambert, Patrik  and  Khalilov, Maxim  and  Fonollosa, José A. R. and  Mariņo, José B.  and  Banchs, Rafael E. (2007): 
Ngram-Based Statistical Machine Translation Enhanced with Multiple Weighted Reordering Hypotheses, Proceedings of the Second Workshop on Statistical Machine Translation 
 
 
 
@InProceedings{rcostajussia-EtAl:2007:WMT,
author = {Costa-juss\`{a}, Marta Ruiz and  Crego, Josep M.  and  Lambert, Patrik  and  Khalilov, Maxim  and  Fonollosa, Jos\'{e} A. R. and  Mariņo, Jos\'{e} B.  and  Banchs, Rafael E.},
title = {Ngram-Based Statistical Machine Translation Enhanced with Multiple Weighted Reordering Hypotheses},
booktitle = {Proceedings of the Second Workshop on Statistical Machine Translation},
month = {June},
address = {Prague, Czech Republic},
publisher = {Association for Computational Linguistics},
pages = {167--170},
url = {
http://www.aclweb.org/anthology/W/W07/W07-0220},
year = 2007
}
 Costa-jussà et al. (2007)
Irina Matveeva and Gina-Anne Levow (2006): 
Computing Term Translation Probabilities with Generalized Latent Semantic Analysis, Proceedings of the 11th Conference of the European Chapter of the Association for Computational Linguistics 
 
 
 
@InProceedings{Matveeva:2006:EACL,
author = {Irina Matveeva and Gina-Anne Levow},
title = {Computing Term Translation Probabilities with Generalized Latent Semantic Analysis},
url = {
http://acl.ldc.upenn.edu/eacl2006/companion/pd/17\_matveeva\_74.pdf},
googlescholar = {10611263447599632007},
booktitle = {Proceedings of the 11th Conference of the European Chapter of the Association for Computational Linguistics},
month = {April},
address = {Trento, Italy},
year = 2006
}
 Matveeva and Levow (2006)