Prague Arabic Dependency Treebank Development in Data and

Prague Arabic Dependency Treebank Development in Data and Tools Faculty of Mathematics and Physics Faculty of Philosophy and Arts Charles University in Prague September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools Jan Hajič Otakar Smrž Petr Zemánek Jan Šnaidauf Emanuel Beška

Project Release – PADT 1. 0 o o December 2004, Linguistic Data Consortium 148 000 Morpho, 113 500 Syntax AFP 13 000 N/A France Presse Penn ATB 1 UMH 38 500 N/A Ummah Press Penn ATB 2 XIN 13 500 N/A Xinhua News A Gigaword ALH 10 000 73 500 Al-Hayat News ANN 12 500 25 500 An-Nahar News A Gigaword XIA 26 500 49 500 Xinhua News September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools A Gigaword 2

Open-Source Tools o Tr. Ed Tree Editor n n o Netgraph Search Engine n n o Multi-purpose annotation environment Suite of programming utilities Server/Client system architecture Easy-to-learn query language Encode: : Arabic Perl Module n n Extension for processing of Arabic script Arab. Te. X, Buckwalter, Unicode, … September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 3

PADT Functional Views o Functional Generative Description n n o Independence of representation levels n n n o Theory of linguistic meaning and its expression Prague Dependency Treebank for Czech Tectogrammatical – linguistic meaning Analytical – surface dependency syntax Morphological – categories and lexical units Abstraction of the relations across levels n n Strict distinction between form and function Different units of description on each level September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 4

Functional Morphology o o o Provides syntax levels with their abstract language, not just giving letters in tokens Revives multiple senses of categories Completeness of generation Strict modeling of grammatical control Morpho. Trees – ‘human tagging’ Successful prototype feature-based tagger September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 5

Syntactic Levels of Description o Analytical level n n n o Pragmatically motivated, close to surface syntax Every single token resulting from morphological level forms one node Tree-like dependency structure for every sentence Tectogrammatical level n n Linguistic (literal) meaning, deep relations, TFA Initial structures transformed from AL Nodes for autosemantic words only Decisive role of valency frames September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 6

Logic of Analytical Trees o o Concepts of dependency and valency Reduction: sentence must retain grammatical correctness if leaves (terminal nodes) are chopped off ¨ Trees: clause components clauses sentences paragraphs etc. Subtrees of clauses exchangeable for non-clauses ¨ Nodes: words, tokenized parts of words, punctuation marks – marked by functions ¨ Edges: syntactic relations – governing node dependent node/subtree September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 7

Some Syntax Issues of Arabic o Non-verbal predication of several types o Subordinate non-verbal clauses / modification o Verb-like behavior of many nominal forms o Mostly VSO in verbal sentences, but… n n o o vice-versa in non-verbal clauses different, depending on context boundness Compound verbs, fixed composite prepositions Grammatical co-reference, accusative of inner object, complex referencing, etc. September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 8

Problem I: Predication o Head node of tree: PREDICATE n o o Why? Steady role in sentence, cannot be omitted Verbal predicate: I-go to school Non-verbal predicate n n n Nominal: The-house a-big (=the house is big) Existential: There a-city (=there is a city) Prepositional o o n Possessive: For him a-house (=he has a house) Adverbial: The-mosque in the-city (=…is…) Conjunctional: The-problem that (=…is that) September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 9

Predication Types in Trees d. Ama [Pred] Nominal lasted kab. Irun [Pnom] a-big [nom. ] iqtir. AHu [Sb] proposal al-baytu [Sb] Prepositional the-house [nom. ] (possessive) vam~ata [Pred. E] there-is la- [Pred. P] for -hu [Obj] him Existential ‑hu al-Eamal. Iyata [Obj] [Atr] the-operation [acc. ] his Prepositional mad. Inatun [Sb] (adverbial, a-city [nom. ] f. I [Pred. P] locative) Verb-like behavior in (object of noun? ) baytun [Sb] a-house [nom. ] September 23, 2004 Verbal al-j. Ami. Eu [Sb] the-mosque [nom. ] Prague Arabic Dependency Treebank: Development in Data and Tools s. AEatayni [Adv] two-hours [acc. ] Eal. A [Aux. P] on zumal. A’i [Obj] colleagues ‑hi [Atr] his al-mad. Inati [Adv] the-city [gen. ] 10

Problem II: Clauses & Co-reference o Recursiveness: subordinate clause is contained as subtree in place of simple element n n n o Head-node of clause gets the same function Problem: non-verbal structures – clauses or not? Compound verbs (m. A z. Ala etc. ) treated equally Grammatical co-reference: Personal pronoun formally required by another element n n n Pronoun must be marked to be treated as such Target of reference is unambiguously identifiable Often in subordinate clauses, mostly attributive Ex. : He-wrote a-book number its-pages hundred September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 11

Compound verb, formed as main verb and its complement Attributive clause, Clauses & Co-reference in Trees z. Alat [Pred] she-stopped prepositional predicate (adverbial) kataba [Pred] he-wrote kit. Aban [Obj] a-book tu. His~u [Atv] al-rajulu [Sb] Objective clause, she-feels f. I [Atr_Pred. P] the-man [nom. ] zaybabu [Sb] verbal predicate in Zaynab Attributive clause, mi’atu [Sb] anna [Aux. C] hundred [nom. ] nominal. Referencing predicate that -hi [Adv_Ref] pronoun, as tu. Ejibu [Obj_Pred] it Saf. Hatin [Atr] attribute in clause they-impress jumalan [Sb] pages [gen. ] sentences [acc. ] m. A [Aux. M] not Referencing na. Hwu [Sb] grammar [nom. ] September 23, 2004 w. ADi. Hun [Atr_Pnom] pronoun, as clear [nom. ] adverbial in clause ‑h. A [Atr_Ref] their Prague Arabic Dependency Treebank: Development in Data and Tools -h. A [Obj] her 12

Future Prospects o o o Implementation of Functional Morphology Tectogrammatical annotation Lexicons of valency frames Re-training the feature-based tagger on Morpho. Trees Machine-learning on the treebank data for various purposes September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 13

Thank you Questions welcome! http: //ckl. mff. cuni. cz/padt/ September 23, 2004 Prague Arabic Dependency Treebank: Development in Data and Tools 14