Eckhard Bick - VISL

Contents
1. INTRODUCTION 8
1.1. The ‘what’s, ‘why’s and ‘who’s 8
1.1. The parser and the text 10
2. THE LEXICOMORPHOLOGICAL LEVEL:STRUCTURING WORDS 15
2.1 A lexical analyser for Portuguese: PALMORF 15
2.2. The program and its data-bases 16
2.2.1. Program specifications 16
2.2.2. Program architecture 17
2.2.2.1. Program modules 17
2.2.2.2. Preprocessing 18
2.2.2.3. Data bases and searching techniques 19
2.2.3. Data structures 22
2.2.3.1. Lexicon organisation 22
2.2.3.2. The inflexional endings lexicon 27
2.2.3.3. The suffix lexicon 29
2.2.3.4.. The prefix lexicon 32
2.2.4. The dynamic lexicon 35
2.2.4.1. Polylexical expressions 35
2.2.4.2. Word or morpheme: enclitic pronouns 39
2.2.4.3. The petebista problem: productive abbreviations 40
2.2.4.4. Names: problems with an immigrant society 41
2.2.4.5. Abbreviations and sentence boundary markers 51
2.2.4.6. The human factor: variations and spelling errors 55
2.2.4.7. Heuristics: The last promille 58
2.2.5. Tagging categories: word classes and inflexion tags 68
2.2.5.1. Defining word classes morphologically 68
2.2.5.2. The individual word classes and inflexional tag combinations 73
2.2.5.3. Portuguese particles 89
2.2.6. Recall: Quantifying the problems 96
3. MORPHOSYNTACTIC DISAMBIGUATION: THE HOLOGRAPHIC PICTURE 99
3.1. The problem of ambiguity: A pragmatic approach 99
3.1.1. Relevant ambiguity 99
3.1.2. Why tags? - The advantages of the tagging notation 113
3.2. Morpological ambiguity in Portuguese 115
3.2.1. Overall morphological ambiguity 115
3.2.2. Word class specific morphological ambiguity 118
3.3. Borderline ambiguity: The limits of form and structure 124
3.4. Word internal (local) disambiguation 129
3.5. Tools for disambiguation 133
3.5.1 Probabilistics: The ‘fire a linguist’ approach 134
3.5.2. Generative Grammar: All or nothing - the competence problem 139
3.5.3. Constraint Grammar: The holographic picture 146
3.6. The rule formalism 151
3.7. Contextual information in constraint building 157
3.7.1. Implicit syntax: Exploiting linear structure 157
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