wsd and meaning - linguistics.byu.edulinguistics.byu.edu/classes/ling654dl/catgra.pdf3...

CATEGORIAL GRAMMAR

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Categorial Grammar• Lexicalized grammatical formalism• Since early 1940’s, mostly in Europe• Type-driven, combinatorial, categorial• Particularly well suited for languages with complex

morphosyntax• Computational implementations

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(Morpho)syntax semantics• The interpretive approach

• Morphology, syntax are prior• Map meaning from: morpho syn sem• Most current linguistic theories

• The tandem approach• Semantics emerges in tandem with morpho, syn• Map meaning while: morpho + syn + sem• Less widely practiced here in North America

A tandem approach• Versus interpretive

• Syntax and semantics in parallel, at the same time

• Can assign categories to morphemes

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Categorial Grammar categories• Basic categories : np, n, and s• Complex categories: composition of basic categories

• α/β is a valid category if α and β are basic or complex categories• α\β is a valid category if α and β are basic or complex categories

• Delimiting slash either backward (\) or forward (/) specifies the appropriate directionality of application

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Backward application

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Forward application

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Example categories (syntax)• determiner: np/n• predicate: s\np• adjective: n/n• verbs: s\np (intrans.), (s\np)/np (trans.)• preposition: (n\n)/np or ((s\np)\(s\np))/np• zero anaphor: np

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Example categories (semantics)• Noun: dog(x)• Intransitive: λP[Psneezed(x)]• Adjective: λP[P & big(x)]

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A parsed sentence

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More categories• complementizer: ((s/np)\(s/np))/s (or just s’)• object relative pronoun: (n\n)/(s/np)• subject relative pronoun: (guess!)

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Type raising• Tom:np

is equivalent to:

• Tom:s/(s\np)

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Incremental parsing

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Another operation• Function composition:

α/β β/γ α/γ

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Implementing a grammar• Attribute Logic Engine (ALE) for instantiating categorial

grammars• Define syntactic categories• Encode lexical items

• Parses and generates sentences

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Sample CG applications• Parsing languages

• Including complex ones: Korean, Turkish, Salish• Modeling human incremental parsing

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Sample NP applications

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S and conjunction

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Turkish example

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Sample rule and parse

tv(Rel) macro rec[7ugWECEd,CEL,ti7E7,hikW,spa7c].synsem:(forward, QSTORE e_listarg:(syn:np, SYNSEM basic

sem:Y), SEM DEFres:(forward, RESTR and

arg:(syn:np, CONJ1 BEARsem:X), ARG1 [0] indiv.

res:(syn:s, CONJ2 BIGsem:(Rel, ARG1 [0]

agent:Y, SCOPE SEEKtheme:X)))), AGENT pro1p

@ quantifier_free. THEME [0]VAR [0]

SYN s

Simple Lushootseed derivation

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Examples (syntax)• English derivations• Lushootseed categories• Lushootseed derivations