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Grounding Ontologies of Linguistic Annotations in the DCR

Grounding Ontologies of Linguistic Annotations in the DCR. Christian Chiarcos chiarcos@uni-potsdam.de. LR&LTS workshop @ LREC 2010, 2010-05-18. Grounding Ontologies of Linguistic Annotations in the DCR. Background repositories of linguistic annotation terminology

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Grounding Ontologies of Linguistic Annotations in the DCR

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  1. Grounding Ontologies of Linguistic Annotations in the DCR Christian Chiarcos chiarcos@uni-potsdam.de LR&LTS workshop @ LREC 2010, 2010-05-18

  2. Grounding Ontologies of Linguistic Annotations in the DCR • Background • repositories of linguistic annotation terminology • An architecture of modular OWL/DL ontologies • OLiA ontologies • Linking OLiA with the DCR

  3. The task • Differences ... among different language resources and individual system objectives ... lead to variations in data category definitions and data category names. • The use of uniform data category names and definitions ... contributes to system coherence and enhances the re-usability of data. (Ide & Romary 2004)

  4. The solution ISO TC37/SC4Data Category Registry (DCR) • ... a family of data category standards designed to meet the needs of terminologists and other language experts developing a variety of electronic linguistic resources. ... • ... to ensure interoperability among these domains ... • ... with an eye to facilitating ... wide-scaleinformation handling environments such as the Semantic Web ... (Wright 2004)

  5. The solution II General Ontology of Linguistic Description (GOLD) • ... large amounts of linguistic data on the Web ... from different languages can be automatically searched and compared ... • ... the data and the various encoding schemes in which they are represented need an explicit semantics. • ... a data model ... which is consistent with .... the Semantic Web ... (Farrar & Langendoen 2003)

  6. The solution III Documentation standards in typology • EUROTYP (Bakker et al. 1993) • AUTOTYP (Bickel & Nichols 2002) • Typological Database System ontology (Dimitriadis et al. 2009) Standardization initiatives and multi-language tagsets • EAGLES (Leech & Wilson 1996) • MULTEXT/East (Erjavec 2004) • Common POS tagset for Indian languages (Baskaran et al. 2008)

  7. Another problem Imagine you plan to develop a tool that makes use of a terminology repository. Which one would you choose ? Similar goals, but different definitions Integration efforts have only just began ... (Marc Kemps-Snijders@SaLTMiL Workshop)

  8. Another problem Imagine you plan to develop a tool that makes use of a terminology repository. Which one would you choose ? Maybe, it‘s not even our choice ... ... our clients may have their own preferences ... and different clients may have different preferences

  9. OLiA architecture Terminology Repositories Terminology Repositories Terminology Repositories • OLiA: Ontologies of Linguistic Annotations • modular architecture of OWL/DL ontologies • „Reference Model“ • interface between annotations and (multiple) terminology repositories Terminology Repositories Terminology Repositories Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models

  10. OLiA ontologies • developed at the Collaborative Research Center (SFB) 632 „Information Structure“ (Potsdam & Berlin) • 2006-2008 in cooperation with Collaborative Research Center (SFB) 441 „Linguistic Data Structures“ (Tübingen) • since 2007 within the SFB 632 project „Linguistic Database“

  11. OLiA ontologies • part of an infrastructure to integrate and access heterogeneous data collections • PAULA format • integrate different formats • ANNIS data base • access data created by different tools • OLiA ontologies • represent tagsets and their semantics in a formal and systematic way

  12. OLiA architecture Terminology Repositories Terminology Repositories Terminology Repositories • annotation schemes formalized in OWL/DL • linked with the „Reference Model“ • concept-based integration • further linked to terminology repositories • „External Reference Models“ Terminology Repositories Terminology Repositories Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models

  13. OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories • a harmonization of repositories of annotation terminology (GOLD, EAGLES, ...) • morphosyntax & morphology • 16 annotation schemes ~ 42 languages* • syntax • 4 annotation schemes ~ 14 languages* • information structure/anaphora (experimental) Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models * including multilingual annotation schemes: Tapainen & Järvinen (1997) and Dipper et al. (2007)

  14. OLiA Reference Model ... ... ... ... Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Morphosyntactic Category Terminology Repositories Terminology Repositories concepts Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories is-a Morphological Feature Numeral is-a OLiA Reference Model is-a Ordinal Number Gender is-a Feminine properties Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories hasGender Terminology Repositories Annotation Models x y x : MorphosyntacticCategory x : Gender

  15. OLiA Annotation Models Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories • OWL/DL formalizations of annotation schemes • structure similar to the Reference Model • values used in annotation represented by individuals • hasTag property • string value of annotation Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models

  16. The Uppsala Annotation Model ... ... ... ... Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories concepts POS Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories is-a Feature Numeral is-a Gender OLiA Reference Model individuals instance_of instance_of instance_of numeral numeral_ord fem Terminology Repositories Terminology Repositories hasTag „numeral...“ hasTag „numeral_ord...“ hasTag „...fem...“ Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models Uppsala corpus tagset, Russian T. Berger, R. Meyer, M. Betsch, University of Tübingen http://www.sfb441.uni-tuebingen.de/b1/en/korpora.html

  17. The Uppsala Annotation Model ... ... ... ... Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories concepts POS Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories is-a Feature Numeral is-a Gender OLiA Reference Model individuals instance_of instance_of instance_of numeral numeral_ord fem Terminology Repositories ... Terminology Repositories hasTag „numeral...“ hasTag „numeral_ord...“ hasTag „...fem...“ Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models Uppsala corpus tagset, Russian T. Berger, R. Meyer, M. Betsch, University of Tübingen http://www.sfb441.uni-tuebingen.de/b1/en/korpora.html numeral_ord_fem_sg_prp numeral _ord _fem_ sg prp второй („second “)

  18. Linking Terminology Repositories Terminology Repositories Terminology Repositories • Annotation model concepts are defined as subclasses of Reference Model concepts • properties as sub-properties • individuals as instances • The linking is physically separated from the models • onepossible interpretation of Annotation Model concepts in terms of the Reference Model Terminology Repositories Terminology Repositories Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models

  19. Linking Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Morphosyntactic Category is-a Numeral OLiA Reference Model is-a is-a Ordinal Number POS is-a instance_of Terminology Repositories Numeral Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models instance_of instance_of numeral numeral_ord hasTag „numeral...“ hasTag „numeral_ord...“ Uppsala Annotation Model

  20. Linking tag-set independent description • rdf:type(olia:Numeral) • rdf:type(olia:OrdinalNumber) • olia:hasGender(olia:Feminine) • etc. annotation numeral_ord numeral numeral_ord_fem_sg_prp _ord _fem_ sg prp hasTag „numeral_ord...“ второй („second “) Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Morphosyntactic Category is-a Numeral OLiA Reference Model is-a is-a Ordinal Number POS is-a instance_of Terminology Repositories Numeral Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models instance_of instance_of instance_of instance_of numeral numeral numeral_ord hasTag „numeral...“ hasTag „numeral...“ hasTag „numeral_ord...“ Uppsala Annotation Model Uppsala Annotation Model

  21. Linking Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories • The OLiA Reference Model can be linked to terminological repositories in the same way • but only if they are modelled in OWL/DL • OWL/DL conversion of the DCR Terminology Repositories Terminology Repositories Terminology Repositories OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models

  22. Linking the DCR an experiment with the morphosyntactic profile • ISOcat (http://www.isocat.org) • 383 data categories organized in 7 directories • PartOfSpeech (115 categories) • Cases (34 categories) • MorphologicalFeaturesExcludingCases (78 cat.s) • RegisterDatingFrequency (19 categories) • other • FormRelated (35 categories) • Operations (29 categories) • Basics (60 categories; unclassified categories)

  23. Linking the DCR • ISOcat export format DCIF • Each data category is assigned • a unique id (e.g., DC-1243) • a textual identifier (e.g., attributiveAdjective) • a definition • Optionally, data categories can be hierarchically structured • dcif:isA (‘has a broader data category’) • dcif:conceptualDomain (‘has one of these values’)

  24. Linking the DCR • DCIF to OWL conversion • XSL/T • data category => owl:Class • definition => rdfs:comment • hierarchical structure => rdfs:subClassOf • reference to DCR: dcr:datcat => valid OWL/DL ... but not an ontology

  25. Linking the DCR Protégé ontology editor

  26. Linking the DCR • semiautomatic linking procedure • for every OLiA Reference Model concept o • if o‘s name matches the name of a DCR concept d, then add o subClassOf d to the linking olia:AttributiveAdjective dcr_owl:attributiveAdjective/DC-1243

  27. Linking the DCR • semiautomatic linking procedure • for every OLiA Reference Model concept o • if o‘s name matches the name of a DCR concept d, then add o subClassOf d to the linking • otherwise, retrieve all DCR concepts whose names contain a word that occurs in the name of o olia:ExclamatoryPronoun dcr_owl:exclamativePronoun/DC-1285

  28. Linking the DCR • semiautomatic linking procedure • for every OLiA Reference Model concept o • if o‘s name matches the name of a DCR concept d, then add o subClassOf d to the linking • otherwise, retrieve all DCR concepts whose names contain a word that occurs in the name of o • manual selection of superconcept d (if there is any) • comment if no candidate is found • manual correction

  29. Linking the DCR • semiautomatic linking • 76 OLiA Reference Model concepts with identical names • for 203 OLiA Reference Model concepts, candidate linkings could be identified • for 155 (76%), one candidate could be confirmed • for 79 concepts, no candidate was found => 231 concepts (64%) linked

  30. Linking the DCR • 35 % of OLiA Reference Model concepts unlinked • gaps • e.g., reflexivity • reflexivePronoun/DC-1378, reflexiveDeterminer/DC-1377 • no reflexivity as a feature of verbs • granularity differences • more detailed subclassification of voice in the OLiA Reference Model • more detailed subclassification of particle/DC-1342 in the DCR

  31. Linking the DCR DCR, OWL/DL version grammaticalGender DC-1297 grammaticalNumber DC-1298 case DC-1840 is-a (dcif:conceptualDomain) feminine DC-1880 locativeCase DC-1326 singular DC-1387 OLiA Reference Model is-a is-a is-a Morphological Feature Terminology Repositories Terminology Repositories is-a is-a is-a Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models Gender Number Case is-a is-a is-a Locative Singular Feminine

  32. Linking the DCR DCR, OWL/DL version partOfSpeech/DC-1345 is-a (dcif:conceptualDomain) attributiveAdjective DC-1243 adjective DC-1230 is-a (dcif:isA) numeral DC-1334 OLiA Reference Model ordinalAdjective DC-1338 is-a is-a Morphosyntactic Category is-a is-a Terminology Repositories is-a is-a Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Numeral Annotation Models Adjective is-a is-a Attributive Adjective Ordinal Number

  33. Linking the DCR tag-set independent description tag-set independent description • rdf:type(dcr_owl:numeral) • rdf:type(dcr_owl:ordinalAdjective) • olia:hasGender(dcr_owl:feminine) • etc. • rdf:type(olia:Numeral) • rdf:type(olia:OrdinalNumber) • olia:hasGender(olia:Feminine) • etc. annotation numeral_ord numeral numeral_ord_fem_sg_prp _ord _fem_ sg prp hasTag „numeral_ord...“ второй („second “) DCR, OWL/DL version OLiA Reference Model Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Terminology Repositories Annotation Models

  34. Conclusion • an architecture that allows • linking annotations with multiple repositories of linguistic annotation terminology • linking with the Data Category Registry => abstraction from annotation-specific representations of linguistic analyses • tagset-independent descriptions with reference to the OLiA Reference Model as well as the DCR

  35. Applications • tag-set independent descriptions • querying heterogeneously annotated resources (Rehm et al. 2007) • interface specifications in NLP pipelines (Buyko et al. 2008) • comparing and combining the output of NLP tools with different annotation schemes (Chiarcos 2010)

  36. Applications • tag-set independent descriptions • querying heterogeneously annotated resources • interface specifications in NLP pipelines • comparing and combining the output of NLP tools • OLiA Reference Model concepts in these applications can be replaced by DCR data categories • as defined in the linking

  37. Thank you for your attention http://nachhalt.sfb632.uni-potsdam.de/owl/olia.owl • additional slides • Example applications • Why ontologies ?

  38. Comparing and combining heterogeneous linguistic analyses* diese nicht neue Erkenntnis [German] this not new insight `this well-known insight‘ Connexor** PRON Dem FEM SG NOM RFTagger*** PRO.Dem.Attr.-3.Acc.Sg.Fem * Chiarcos, Ch. (2010), Towards robust multi-tool tagging. An OWL/DL-based approach. to be presented at ACL-2010, Uppsala, Sweden, June 2010 ** P. Tapanainen and T. Järvinen. 1997. A nonprojective dependency parser. In Proceedings of the 5th Conference on Applied Natural Language Processing, pages 64–71, Washington, DC, April 1997 *** H. Schmid and F. Laws. 2008. Estimation of conditionalprobabilities with decision trees and an application to fine-grained pos tagging. In Proceedings of the 22nd International Conference on Computational Linguistics (COLING 2008), Manchester, UK, August 2008.

  39. Comparing and combining heterogeneous linguistic analyses OLiA Reference Model descriptions rdf:type(olia:PronounOrDeterminer) rdf:type(olia:Pronoun) rdf:type(olia:DemonstrativePronoun) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) olia:hasCase(olia:Nominative) rdf:type(olia:PronounOrDeterminer) rdf:type(olia:Determiner) rdf:type(olia:DemonstrativeDeterminer) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) olia:hasCase(olia:Accusative) Connexor PRON Dem FEM SG NOM RFTagger PRO.Dem.Attr.-3.Acc.Sg.Fem

  40. Comparing and combining heterogeneous linguistic analyses OLiA Reference Model descriptions rdf:type(olia:PronounOrDeterminer) rdf:type(olia:Pronoun) rdf:type(olia:DemonstrativePronoun) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) olia:hasCase(olia:Nominative) rdf:type(olia:PronounOrDeterminer) rdf:type(olia:Determiner) rdf:type(olia:DemonstrativeDeterminer) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) olia:hasCase(olia:Accusative) Connexor PRON Dem FEM SG NOM RFTagger PRO.Dem.Attr.-3.Acc.Sg.Fem

  41. Comparing and combining heterogeneous linguistic analyses OLiA Reference Model descriptions rdf:type(olia:PronounOrDeterminer) rdf:type(olia:Pronoun) rdf:type(olia:DemonstrativePronoun) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) olia:hasCase(olia:Nominative) rdf:type(olia:PronounOrDeterminer) rdf:type(olia:Determiner) rdf:type(olia:DemonstrativeDeterminer) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) olia:hasCase(olia:Accusative) confidence ranking rdf:type(olia:PronounOrDeterminer) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) rdf:type(olia:Pronoun) rdf:type(olia:Determiner) rdf:type(olia:DemonstrativePronoun) rdf:type(olia:DemonstrativeDeterminer) olia:hasCase(olia:Accusative) olia:hasCase(olia:Nominative) predicted by both tools predicted by one tool

  42. Comparing and combining heterogeneous linguistic analyses disambiguation: create the maximal consistent set S of descriptions • S is empty • process descriptions with decreasing confidence • if the current description is consistent with all descriptions in S, then add it to S • if not, skip it • iterate until all descriptions are processed confidence ranking rdf:type(olia:PronounOrDeterminer) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) rdf:type(olia:Pronoun) rdf:type(olia:Determiner) rdf:type(olia:DemonstrativePronoun) rdf:type(olia:DemonstrativeDeterminer) olia:hasCase(olia:Accusative) olia:hasCase(olia:Nominative) predicted by both tools predicted by one tool

  43. Comparing and combining heterogeneous linguistic analyses disambiguation: create the maximal consistent set S of descriptions • S is empty • process descriptions with decreasing confidence • if the current description is consistent with all descriptions in S, then add it to S • if not, skip it • iterate until all descriptions are processed consistency rdf:type(olia:PronounOrDeterminer) olia:hasNumber(olia:Singular) olia:hasGender(olia:Feminine) rdf:type(olia:Pronoun) rdf:type(olia:Determiner) rdf:type(olia:DemonstrativePronoun) rdf:type(olia:DemonstrativeDeterminer) olia:hasCase(olia:Accusative) olia:hasCase(olia:Nominative) can be defined in the ontology e.g., assume that all concepts are disjoint (inconsistent) unless one is a subconcept of the other

  44. Ontology-based corpus querying corpus query ... pos in { type(Noun) and ...} & cat = ... Noun CommonNoun Substantive • ontology lookup: • retrieve instances • and tags • 2. application of set • operators linking ProperNoun Nominal MassNoun CountableNoun VerbalNoun Reference Model tibet: CommonNoun tibet: ProperNoun tibet: InanimateNoun tibet: AnimateNoun tibet: Person NAME NOM_inan NOM_pers NOM_pers_anim NOM_inan_lq NOM_anim NOM_anim_lq Annotation Model ... pos = NN | pos = NCOM | pos = substantiv_masc_pl_dat_bel |pos = substantiv_masc_pl_akk_unb | pos = substantiv_fem_sg_ins_unb & cat = ... return modified corpus query

  45. Why ontologies ? Integration with Semantic Web technologies and resources e.g., Hellmann (2010) S. Hellmann. 2010. The semantic gap of formalized meaning. to be presented at The 7th Extended Semantic Web Conference (ESWC 2010), Heraklion, Greece, May 31st

  46. Why ontologies ? • Ontology linking instead of annotation mapping • Mapping is 1:1 or 1:n • But what does 1:n mean ? (a) ambiguity => logical „or“ • SUSANNE tag ICSt „after as preposition or conjunction“ • only one of these possibilities is correct (b) overlap => logical „and“ • palace in Buckingham Palace is (part of a) proper name • but it is used in its literal meaning => common noun • OWL/DL: join ≠ intersection

  47. References Bakker, D. et al. (1993), Eurotyp Guidelines, http://www-uilots.let.uu.nl/ltrc/eurotyp/index.htm Baskaran, S. et al. (2008), A Common Parts-of-Speech Tagset Framework for Indian Languages, LREC 2008 Bickel, B. and Nichols, J. (2002), Autotypologizing databases and their use in fieldwork, LREC 2002 Buyko, E., C. Chiarcos, and A. Pareja-Lora. 2008. Ontology-based interface specifications for a NLP pipeline architecture. LREC 2008 Chiarcos, Ch., S. Dipper, M. Götze, U. Leser, A. Lüdeling, J. Ritz, and M. Stede (2008). A Flexible Framework for Integrating Annotations from Different Tools and Tagsets. TAL (Traitement automatique des langues), 49(2). Chiarcos, Ch., J. Ritz, and M. Stede (2009). By all these lovely tokens...: Merging conflicting tokenizations. Third Linguistic Annotation Workshop (LAW III) held in conjunction with ACL-IJCNLP 2009, Singapore Chiarcos, Ch. (2010), Towards robust multi-tool tagging. An OWL/DL-based approach. to be presented at ACL-2010, Uppsala, Sweden, June 2010 Dimitriadis, A. et al. (2009), How to Integrate Databases without starting a typology war: The Typological Database System. In: Martin Everaert et al. (eds.), The Use of Databases in Cross-Linguistic Studies. Berlin: Mouton de Gruyter. Dipper, S. and M. Götze (2005). Accessing heterogeneous linguistic data. Generic XML based representation and flexible visualization. Second Language & Technology Conference 2005, pages 23–30, Poznan, Poland, April 2005

  48. References Dipper, S., M. Götze, and S. Skopeteas, editors (2007). Information Structure in Cross-Linguistic Corpora: Annotation Guidelines for Phonology, Morphology, Syntax, Semantics, and Information Structure. Interdisciplinary Studies on Information Structure (ISIS), Working Papers of the SFB 632 (7) Erjavec, T. (2004), MULTEXT-East version 3: Multilingual morphosyntactic specifications, lexicons and corpora, LREC 2004 Ide, N. and Romary, L. (2004), A registry of standard data categories for linguistic annotation. LREC 2004 Farrar, S. and Langendoen, D.T. (2003), A linguistic ontology for the semantic web. Glot International 7(3) Leech, G. and Wilson, A. (1996), EAGLES recommendations for the morphosyntactic annotation of corpora. EAGLES Document EAG-TCWG-MAC/ R Rehm, G., R. Eckart, and C. Chiarcos. 2007. An OWL- and XQuery-based mechanism for the retrieval of linguistic patterns from XML-corpora. RANLP 2007 Schmidt, T. et al. 2006. Avoiding data graveyards: From heterogeneous data collected in multiple research projects to sustainable linguistic resources. E-MELD workshop on Digital Language Documentation, East Lansing US, June 2006. Tapanainen P. and T. Järvinen. 1997. A nonprojective dependency parser. In Proceedings of the 5th Conference on Applied Natural Language Processing, pages 64–71, Washington, DC, April 1997 Wright, S.E. (2004), A Global Data Category Registry for Interoperable Language Resources, LREC 2004 Zeldes, A., J. Ritz, A. Lüdeling & C. Chiarcos (2009), "ANNIS: A Search Tool for Multi-Layer Annotated Corpora". In: Proceedings of Corpus Linguistics 2009, July 20-23, Liverpool, UK.

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