Minimalist Grammars Formalisme en Dependency Structures Sjoerd Dost - - PowerPoint PPT Presentation

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Minimalist Grammars Formalisme en Dependency Structures Sjoerd Dost - - PowerPoint PPT Presentation

The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Minimalist Grammars Formalisme en Dependency Structures Sjoerd Dost Myrthe Tielman Logical Methods in NLP 03/05/12 Dost, Tielman


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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Minimalist Grammars

Formalisme en Dependency Structures Sjoerd Dost Myrthe Tielman Logical Methods in NLP 03/05/12

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Inhoud

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The Minimalist Program

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Minimalist Grammars Lexicon

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Merge Merge Move

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Onion

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Dependency Structures Aim Merge1 Merge2 and 3 Move1 Move2

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Block Degree

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Nestedness

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

The Minimalist Program

Chomsky, Universal Grammar

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

The Minimalist Program

Chomsky, Universal Grammar ”effort to attribute as little as possible to UG while still accounting for the apparent diversity of human languages” (Stabler, 2011)

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

The Minimalist Program

Chomsky, Universal Grammar ”effort to attribute as little as possible to UG while still accounting for the apparent diversity of human languages” (Stabler, 2011) Endocentricity

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Endocentricity

”A head X determines certain relevant properties of the phrase XP it is the head of.” Merging head x with xy gives {x{xy}}

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Lexicon

Lexicon

Stabler 2010: Computational perspectives on minimalism A minimalist grammar G is a lexicon: G ⇢ PhoneticFeatures x Features*, a finite set Where Features* is the set of finite sequences of syntactic features Where the elements of the lexicon are combined by the merge

  • peration. (Stabler, 2011)

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Lexicon

Features

Features: Categorial N, V , A, P, C, T, D, . . .

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Lexicon

Features

Features: Categorial N, V , A, P, C, T, D, . . . Selector = N, = V , = A, = P, = C, = T, = D, . . .

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Lexicon

Features

Features: Categorial N, V , A, P, C, T, D, . . . Selector = N, = V , = A, = P, = C, = T, = D, . . . Licensee (goal) wh, case, . . .

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Lexicon

Features

Features: Categorial N, V , A, P, C, T, D, . . . Selector = N, = V , = A, = P, = C, = T, = D, . . . Licensee (goal) wh, case, . . . Licensor (probes) +wh, +case, . . .

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Lexicon

Example Lexicon

Who Marie praises? Marie :: D who :: D -wh praises :: =D =D V ε :: =T +wh C

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge

From lexical items to trees

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge

From lexical items to trees Lexical items are 1 node trees

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge

From lexical items to trees Lexical items are 1 node trees Merge (external merge) and Move (internal merge)

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge

From lexical items to trees Lexical items are 1 node trees Merge (external merge) and Move (internal merge) Merge to merge 2 trees together

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge

From lexical items to trees Lexical items are 1 node trees Merge (external merge) and Move (internal merge) Merge to merge 2 trees together Move to restructure trees

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge rule

em(t1[= x], t2[x]) =              < t1 t2 if |t1| = 1 > t2 t1

  • therwise

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Merge rule

Merge (external merge) praises::=D =D V + Pierre::D ! < praises:=D V Pierre < praises:=D V Pierre + Marie::D ! > Marie < praises:V Pierre

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Move

Move (internal merge) SMC: Exactly one head in the tree has -x as its first feature.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Move

Move (internal merge) SMC: Exactly one head in the tree has -x as its first feature. t{t1 7! t2} : the result of replacing subtree t1 by t2 in t.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Move

Move (internal merge) SMC: Exactly one head in the tree has -x as its first feature. t{t1 7! t2} : the result of replacing subtree t1 by t2 in t. tM : the maximal projection of the head of t.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Move

Move (internal merge) SMC: Exactly one head in the tree has -x as its first feature. t{t1 7! t2} : the result of replacing subtree t1 by t2 in t. tM : the maximal projection of the head of t. A subtree is a maximal projection, if it is not properly included in any larger subtree that has the same head.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Move

im(t1[+x]) = > tM2 t1{t2[x]M 7! ε} if SMC.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Move

Move (internal merge) < ε:+wh C > Marie < praises < which:-wh student

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Merge Move

Structuurregels

Move (internal merge) > < which student < ε:C > Marie < praises ε

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Onion

CMG = Conflated Minimalist Grammar, PMG = Phase-based Minimalist Grammar, RMG = Relativized Minimalist Grammar, MCFG = Multiple Context-free Grammar

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2

”An interpretation of Minimalist Grammars in terms of dependency structures.” (Boston, Hale Kuhlmann 2010)

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2 Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Aim Merge1 Merge2 and 3 Move1 Move2

(SMC) None of α1, ..., αi−1, αi+1, ..., αk has -f as its first feature.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Projectivity: subtrees span intervals

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Projectivity: subtrees span intervals Non-projective structures violate this constraint

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Projectivity: subtrees span intervals Non-projective structures violate this constraint Block degree: maximum number of intervals spanned

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Merge always forms dependency relations between roots of subtrees by construction

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Merge always forms dependency relations between roots of subtrees by construction Move1 can create non-projective structures

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness

Merge always forms dependency relations between roots of subtrees by construction Move1 can create non-projective structures Movement is triggered by lincensor-licensee pairs: block degrees bounded by #licensees

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Wellnestedness Illnested structures

Wellnested structures prohibit thecrossing of disjoint subtree intervals.

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Wellnestedness Illnested structures

Wellnested structures prohibit thecrossing of disjoint subtree intervals. Not all mildly context-sensitive formalisms can derive illnested structures (i.e. TAG).

Dost, Tielman Minimalist Grammars

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The Minimalist Program Minimalist Grammars Merge Onion Dependency Structures Block Degree Nestedness Wellnestedness Illnested structures

MGs can derive illnested structures (see example)

Dost, Tielman Minimalist Grammars