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Prague Dependency Treebank 1.0. Functional Generative Description. Functional Generative Description. theoretical framework based on the findings of European structural linguistics, esp. of the classical Prague School methodological requirements of a formal description levels :
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Prague Dependency Treebank 1.0 Functional Generative Description
Functional Generative Description • theoretical framework based on the findings of European structural linguistics, esp. of the classicalPrague School • methodological requirements of aformal description • levels: • tectogrammatical (underlying) representations (TRs) withdependency based syntax • morphemics • phonemics and phonetics • TRs(see Sgall, Hajičová and Panevová 1986, formally specified by Petkevič, also in a declarative way)
The Language Layers • Phonemic, • Morphonological, • Morphemic, • Analytical (surface syntax) • Tectogrammatical (deep syntax).
Dependency tree My younger brother arrived there yesterday. Linearized form, one-to-one relation: ((I)Appurt (younger)Rstr brother)Act arrive.Pret.Indic (Dir there) (Temp yesterday)
Dependency Tree • labels - lexical meanings (abstract symbols) with indices • functors • subscripts at parentheses oriented towards head • grammatemes - values of morphological categories • Tense, Modality, Number, Definiteness, etc. • projectivity • valency • arguments (inner participants) and adjuncts (circumstantials or 'free modifications') • obligatoryandoptional with a given head, • deletable or not
Dependency Tree • Arguments/participants of verbs • Actor/Bearer (underlying subject) • Objective (Patient, underlying direct object) • Addressee(underlying indirect object) • Effect ('second' object: to choose so. as sth.) • Origin(to make sth. out of sth.) • Adjuncts • Locative, several Directional and Temporal modifications • Condition, Means, Manner, etc.
Arguments (inner participants) Material (Partitive) two baskets of sth. Identitythe river Danube; the notion of operator Adjuncts (free modifications) Possession (Appurtenance) my table; Jim's brother Restrictive rich man Descriptive the Swedes, who are a Scandinavian nation Dependency Tree Complementations dependent mainly on nouns
Dependency Tree • syntactic grammatemes • Loc, Dir - in, on, under, between... • Regard - with, without • operational (testable) criteria • for distinguishing • arguments from adjuncts, • from each other • deletability (dialogue test)
Simplified valency frames • read V Act Addr Obj • change V ActObj Orig Eff • give V ActAddrObj • brother N Appurt • man N • glass N Material • full A Material obligatory complementations in blue
T there young Topic-focus articulation • contextual boundness • main verb CB/NB (T/F) • dependents to the left/right • communicative dynamism • left-right (mother, sisters, transitive) • partial ordering • underlying word order • left-right • linear ordering left-to-right order of nodes together with the index T or (prototypically) F indicates the TFA of the sentence (of the TR)
T F there yesterday young Topic-focus articulation • TFA - one of the basic aspects of underlying structures
Complex sentence • a subordinated (dependent) clause (i.e. its main verb) depends on a word contained in its governing clause My brother, whom you know, arrived there yesterday.
Complex sentence • functionwords (synsemantic)are viewed as function morphemes, syntactically fixed to certain lexical (autosemantic) words - prepositions and articles to nouns, conjunctions and auxiliaries to verbs Martin came there late, since he had to accompany his sick mother.
Complex sentence Martin arrived late to the session, since he had to accompany his sick mother.schematically (morphemes): Martin arrive.ed late to the session since he have.ed to accompany he.s sick mother.dot - close connection of morphemes ('semes')
deleted items restored • order of items - difference between 'underlying' and surface (morphemic) word order • transductive components - Panevová, Oliva, Borota • coordination (multidimensional) • Jim and Mary, who have two children, went to Boston. • the linearized notation is adequate: • ((Jim Mary)Conj ((who)Act have (Pat (two)Rstr children)))Act went (Dir Boston) • structures close to Boolean, i.e.no complex'innate properties' specific for natural language are needed.
Prague Dependency Treebank - corpus annotation • an intermediate level - 'analytical' representations • dependency trees, not always projective • nodes for all word tokens, even for punctuation marks • tectogrammmatical tree: coordinating conjunction as the head
Prague Dependency Treebank 1.0 Morphological Layer
ANNOTATED CORPORA PDT version 1.0, 2000 (1996 - 2000) (currently) ver. 2 Penn Treebank, release 3, 1999 (1989 - 1999) PropBank (currently)
The Levels in PDT • Morphemic • Analytical • Tectogrammatical
TAG SETs Czech - ambiguous inflective language nový, nového, novému, novém, novým, nová, nové, novou, nových, novým, novými, … novější, novejšího, novějšímu, novějším, …., nejnovější, nejnovějšího, nejnovějšímu, nejnovějším….. nejnovějších, nejnovějším, … English -language with poor inflection work, works, worked, working
Lidové noviny Mladá Fronta Dnes Vesmír Českomoravský Profit ...taken from Czech National Corpus ´88, ´89 WSJ articles Air Travel Information System transcripts Brown Corpus Switchboard transcripts TEXT SOURCES
ANNOTATION STRATEGY - Penn Treebank TEXT Ken Church‘s stochastic tagger, Eric Brill‘s transformation tagger corrections by annotator (GNU Emacs Lisp based package)
Automatic Morphological Analyzer (AMA) two independent annotators;Linux, Win tools differences resolved by third annotator comparison with the current AMA; manual resolution; Win tools ANNOTATION STRATEGY - PDT
SGML coding, csts dtd word/tag(|tag)* INTERNAL FORMAT
SAMPLES <s id=“ln95040:020-p1s1“> <f>Pokus<l>pokus<t>NNIS1-----A---- <f>o<l>o<t>RR--4---------- <f>zázrak<l>zázrak<t>NNIS4-----A---- <d>.<l>.<t>Z:------------- The/DT envelope/NN arrives/VBZ in/IN the/DT mail/NN ./.
SGML coding SGML coding word/tag word/lemma/tag CONVERSION pdt2wsj.pl pdt2wsjFLT.pl
Automatic Morphological Analyser/Generator of Czech HMAnalyze.pl, HMGenerate.pl Dictionary: CZE_a Remote Access Czech Taggers HMM Exponential TOOLS
Prague Dependency Treebank 1.0 Analytical Layer in PDT
Introduction • Input: morphologically tagged sentences • Graph Editor: “user-friendly” software • Output: ATS structure • „surface“ syntax tree structure • nodes labelled by the analytical functions
Analytical Functions • Pred - Predicate if it depends on the tree root • Sb - Subject • Obj - Object • Adv - Adverbial • Atv - Complement • AtvV - Complement, if one governor is present • Atr - Attribute • Pnom - Nominal predicate‘s nominal part, depends on the copula „to be“ • AuxV - Auxiliary verb „to be“ • Coord - Coordination node • Apos - Apposition node • AuxR - Reflexive particle, which is neither Obj nor AuxT (passive) • AuxT - Reflexive particle, lexically bound to the verb
Analytical Functions • AuxP - Preposition or a part of compound preposition • AuxC - Subordinate conjunction • AuxO - (Superfluously) referring particle or emotional particle • AuxZ - Rhematizer or another node acting to another constituent • AuxX - Comma, but not the main coordinating comma • AuxG - Other graphical symbols being not classified as AuxK • AuxY - Other words, such as particles without a specific syntactic function, parts of lexical idioms, etc. • AuxS - Sentence holder (the only added root to the tree) • AuxK - Punctuation at the end of the sentence or direct speech or citation clause • ExD - Ellipsis handling: functions for nodes which pseudo depend on a node on which the would not depend if there were no ellipsis • AtrAtr, AtrAdv, AdvAtr, AtrObj, ObjAtr + *_Co, *_Pa, *_Ap
Two stages (chronologically) • (A) manual „analytic“ annotation (ATS) • training data for (B)(a) • (B) • (a) semiautomatic procedure (Collin‘s parser) • (b) manual correcting of (B)(a)
Constraints and limitations • any string has a node of its own • word-form, punctuation mark, etc. • AuxV, AuxP, AuxC, AuxX, AuxG… • reflecting the coordination and apposition relations • so called third dimension of the graph in the plain tree (X_Co, X_Ap, X_Pa, where X is one of analytic functions, such as Sb, Obj, Adv, etc.)
Constraints and limitations • no missing nodes (on the surface) can be added • analytic funtion Ex_D is used • relations between semi-automatic and manual procedure • 80% edges are established correctly automatically
Project organization • team consisting of 5-6 annotators • handbook for ATS structure annotation • 100000 sentences on ATS • tectogrammatical annotation follows
Projectivity/Nonprojectivity/Surface Order • A(B, C) A A A C C B B B C
Projectivity/Non-projectivity/Surface Order • A(B( C )) A A A B B B C C C
AuxT Adv První restituční zákon českého parlamentu se do sněmovních lavic může vrátit jako bumerang.
Prague Dependency Treebank 1.0 From the Analyticaltowards the Tectogrammatical layer
Introduction • ATS annotation • nodes: • word forms • punctuation • graphical symbols • TGTS annotation • autosemantic words • deletions • edges: • surface relations • deep layer functions
Tokenization ATS PDT1.0 Morphological tagging and lexical disambiguation Syntactic parsing and analytic function assignment TGTS Tree structure pruning Attribute assignments Annotation process Input Czech sentence
Transition procedure • deterministic procedure operating on trees • macro language for Graph Editor (perl) • automatic changes & tools for annotators • Requirements • new attributes for tectogrammatical layer • ATS is recoverable from TGTS • automatized to a maximally high degree
New attributes • trlemma - lemmaof the original node or lemma composed of joined nodes • morphological grammatemes • gender, number, degree of comparison, tense, • aspect, iterativeness, verbal modality, deontic modality, sentence modality • positionof the node • functor, topic-focus articulation, syntactic grammateme, • type of relation (dependency, coordination, apposition), • phraseme, deletion, quoted word, direct speech, • coreference, antecedent
Tree Structure Pruning • U toho, kdo začíná opravdu od nuly, není daňový výnos pro stát podstatný. • For those, who start actually at zero, the tax outcome for the state is not substantial.
REG Tree Structure Pruning • U toho, kdo začíná opravdu od nuly, není daňový výnos pro stát podstatný. • For those, who start actually at zero, the tax outcome for the state is not substantial.
verbmod=CDN deontmod=HRT PRED Verbal Nodes • … podnikatelé by měli mít daně … • … enterpreneurs should have (their) taxes …
Attribute Assignments • prepositions stored as fwattribute • quoted words • clause in quotes -> DSP • one pair of quotes in the sentence -> DSPP • string in quotes -> QUOT • gender, number, tense, degcmp, aspect • default values