Discourse-Givenness of Noun Phrases Theoretical and Computational Models
Total Page:16
File Type:pdf, Size:1020Kb
Discourse-Givenness of Noun Phrases Theoretical and Computational Models Dissertation zur Erlangung des akademischen Grades Doktor der Philosophie (Dr. phil.) der Humanwissenschaftlichen Fakult¨at der Universit¨atPotsdam vorgelegt von Julia Ritz Stuttgart, Mai 2013 Published online at the Institutional Repository of the University of Potsdam: URL http://opus.kobv.de/ubp/volltexte/2014/7081/ URN urn:nbn:de:kobv:517-opus-70818 http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-70818 Erkl¨arung(Declaration of Authenticity of Work) Hiermit erkl¨areich, dass ich die beigef¨ugteDissertation selbstst¨andigund ohne die un- zul¨assigeHilfe Dritter verfasst habe. Ich habe keine anderen als die angegebenen Quellen und Hilfsmittel genutzt. Alle w¨ortlich oder inhaltlich ¨ubernommenen Stellen habe ich als solche gekennzeichnet. Ich versichere außerdem, dass ich die Dissertation in der gegenw¨artigenoder einer an- deren Fassung nur in diesem und keinem anderen Promotionsverfahren eingereicht habe, und dass diesem Promotionsverfahren keine endg¨ultiggescheiterten Promotionsverfahren vorausgegangen sind. Im Falle des erfolgreichen Abschlusses des Promotionsverfahrens erlaube ich der Fakult¨at, die angef¨ugtenZusammenfassungen zu ver¨offentlichen. Ort, Datum Unterschrift iii iv iv Contents Preface xiii 1 Introduction 1 1.1 Discourse-Givenness and Related Concepts . .3 1.2 Goal . .4 1.3 Motivation . .6 1.4 The Field of Discourse-Givenness Classification . 10 1.5 Structure of this Document . 11 2 Concepts and Definitions 13 2.1 Basic Concepts and Representation . 13 2.1.1 Basic Concepts in Discourse . 14 2.1.2 Formal Representation . 15 2.2 Reference . 18 2.2.1 Identifying Basic Units . 20 2.2.2 Non-Referring Use of Expressions . 24 2.2.3 World of Reference . 25 2.2.4 Specificity . 27 2.2.5 Generalizations . 29 2.2.6 Vagueness and Ambiguity . 33 2.3 Coreference . 35 2.3.1 Consequences of Vagueness, Ambiguity and Non-Specificity . 36 2.3.2 Coreference vs. Lexical, Intensional or Extensional Identity . 37 2.3.3 Identity of Binding Index . 39 2.3.4 Asserted Identity . 42 2.3.5 Identity and Time Dependence . 45 2.3.6 Accommodation of Referents . 45 2.3.7 Bridging . 46 2.4 Coreference, Discourse-Givenness and Information Status . 48 3 Corpora and Annotation Schemes 53 3.1 Corpora Annotated with Discourse-Givenness or Coreference . 53 3.1.1 MUC-7 . 54 3.1.2 Nissim's Annotation of the Switchboard Corpus . 55 3.1.3 OntoNotes . 55 3.1.4 ARRAU . 55 v vi 3.1.5 PCC . 56 3.1.6 T¨uBa-D/Z. 56 3.1.7 DIRNDL . 57 3.2 Comparison of Annotation Schemes . 57 3.2.1 Markables and Preconditions . 58 3.2.1.1 Markables . 58 3.2.1.2 Preconditions . 68 3.2.2 Coreference and Context . 69 3.2.2.1 Discourse-Givenness and Coreference . 69 3.2.2.2 Notions of Context . 74 3.2.3 Formalization and Evaluation of the Annotation . 74 3.2.3.1 Formalization . 74 3.2.3.2 Evaluation . 75 3.2.4 A Critical Assessment of Existing Corpora . 77 4 Related Work and Technical Background 81 4.1 Data and Categories . 81 4.2 Features . 83 4.2.1 Properties of NPs . 83 4.2.2 NPs' Relations to their Context . 85 4.3 Algorithms . 87 4.3.1 Evaluation Measures . 93 4.4 Experiments and Results . 95 5 Discourse-Givenness Classification: New Experiments and Results 101 5.1 Data . 101 5.2 Methods . 102 5.2.1 Features . 102 5.2.2 Algorithms and Evaluation Measures . 109 5.3 Classification Results . 110 5.3.1 Quantitative Results . 110 5.3.1.1 OntoNotes . 110 5.3.1.2 MUC-7 . 116 5.3.1.3 ARRAU . 123 5.3.1.4 T¨uBa-D/Z . 126 5.3.2 Discussion . 132 5.3.2.1 Machine Learning Aspects . 132 5.3.2.2 Linguistic Aspects . 134 5.4 Comparison to Related Work . 135 5.4.1 OntoNotes . 136 5.4.2 MUC-7 . 136 5.4.3 Related Work in General . 136 6 Conclusions and Outlook 139 6.1 Conclusions . 139 6.2 Outlook . 140 vi vii 7 Summaries 143 7.1 Summary in English . 143 7.2 Summary in German (Zusammenfassung in deutscher Sprache)...... 146 References 150 Index 166 vii viii viii List of Figures 1 Coreference visualisation in ANNIS2 . xiv 1.1 Example Discourse . .1 1.2 Example Structure according to Rhetorical Structure Theory (RST) . .9 1.3 Coreference Resolution: Terminology . 10 2.1 DRS of `Jones owns Ulysses. It fascinates him.' . 16 2.2 DRS of `Susan has found every book which Bill needs. They are on his desk.' . 17 2.3 DRS of `Most students bought books that would keep them fully occupied during the next two weeks.' . 17 2.4 DRS of `Mary wants to marry a rich man. He is a banker.' . 26 2.5 DRS of `Mary wants to marry a rich man. He must be a banker.' . 26 2.6 DRS of `If parents are dissatisfied with a school, they should have the option of switching to another.' . 27 2.7 DRS of `Parents should have the option of switching to another school, if they are dissatisfied with the current school.' . 27 2.8 DRS of `Jones does not own a Porsche.' . 30 2.9 DRS of `A wolf takes a mate for life.' . 30 2.10 DRS of `Sheep are quadrupedal, ruminant mammals typically kept as live- stock. Sheep are members of the order Artiodactyla.' . 33 2.11 Syntactic Tree Containing Traces . 42 2.12 DRS for `John took Mary to Acapulco. They had a lousy time.' . 46 2.13 DRS for `The students went camping. They enjoyed it.' . 47 2.14 Prince's (1981) Hierarchical Scheme of Familiarity . 49 2.15 Information Status, Discourse Status, and Hearer Status . 50 3.1 Syntactic Analysis of Possessives in MUC-7 . 60 3.2 Syntactic Analysis of Possessives in OntoNotes 1.0 . 60 3.3 Syntactic analysis of a PP with Fusion of Preposition and Definite Determiner 63 4.1 Example Decision Tree for Discourse-Givenness. 88 4.2 Pseudo-code for Decision Tree Construction . 88 4.3 Example Rules for Discourse-Givenness. 89 4.4 Pseudo-code for Rule Learners . 89 4.5 Support Vector Machines . 91 5.1 OntoNotes 1.0: Decision Tree . 113 ix x 5.2 OntoNotes 1.0: Learning Curve . 114 5.3 MUC-7: Decision Tree . 118 5.4 MUC-7: Learning Curve (original split) . 120 5.5 MUC-7: Learning Curve (random split) . 122 5.6 MUC-7: Learning Curve (all vs. Formaleval) . 122 5.7 ARRAU 1.2: Learning Curve . 124 5.8 ARRAU 1.2: Decision Tree . 125 5.9 T¨uBa-D/Z6.0: Learning Curve . 129 5.10 T¨uBa-D/Z6.0: Decision Tree (coreferential/anaphoric/bound) . 130 5.11 T¨uBa-D/Z6.0: Decision Tree (coreferential) . 131 x List of Tables 2.1 Types of Reference (Tentative) . 19 2.2 Specificity, Genericity and Coreference . 32 2.3 Concepts and Definitions . 51 3.1 Overview of Corpora Annotated with Coreference/Discourse-Givenness . 54 3.2 Markable Definitions (part I: English Corpora) . 64 3.2 Markable Definitions (part II: German Corpora) . 66 3.3 Definitions of Coreference (part I: English Corpora) . 70 3.3 Definitions of Coreference (part II: German Corpora) . 72 4.1 Overview: Approaches to Identifying Information Structure . 82 4.2 Comparison of Learning Algorithms . 92 4.3 Naming Conventions for Evaluation . 93 4.4 Example Contingency Table . 95 4.5 State of the Art Classification Results (part I) . 96 4.5 State of the Art Classification Results.