SLIDE 1 From Tree Adjoining Grammars to Higher Order Representations of Abstract Meaning Representations via Abstract Categorial Grammars
Rasmus Blanck, Aleksandre Maskharashvili
Centre for Linguistic Theory and Studies in Probability, University of G¨
29 August 2018 Symposium on Logic and Algorithms in Computational Linguistics Stockholm, Sweden
SLIDE 2
Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
2
SLIDE 3 Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
◮ semantic treebank ◮ de-languagized (still biased towards English) ◮ used for semantic parsing (Artzi, Lee, and Zettlemoyer, 2015) and generation (Flanigan
et al., 2016)
◮ limitations: (universal) quantification, negation
2
SLIDE 4 Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
◮ semantic treebank ◮ de-languagized (still biased towards English) ◮ used for semantic parsing (Artzi, Lee, and Zettlemoyer, 2015) and generation (Flanigan
et al., 2016)
◮ limitations: (universal) quantification, negation ◮ recent developments:
AMRs were transformed as FOL formulas (Bos, 2016) AMRs were transformed as HOL formulas modeling event semantics (Stabler, 2018) problems of quantification, negation were overcome . . . 2
SLIDE 5 Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
◮ semantic treebank ◮ de-languagized (still biased towards English) ◮ used for semantic parsing (Artzi, Lee, and Zettlemoyer, 2015) and generation (Flanigan
et al., 2016)
◮ limitations: (universal) quantification, negation ◮ recent developments:
AMRs were transformed as FOL formulas (Bos, 2016) AMRs were transformed as HOL formulas modeling event semantics (Stabler, 2018) problems of quantification, negation were overcome . . .
Tree Adjoining Grammars (TAGs) (Joshi, Levy, and Takahashi, 1975)
2
SLIDE 6 Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
◮ semantic treebank ◮ de-languagized (still biased towards English) ◮ used for semantic parsing (Artzi, Lee, and Zettlemoyer, 2015) and generation (Flanigan
et al., 2016)
◮ limitations: (universal) quantification, negation ◮ recent developments:
AMRs were transformed as FOL formulas (Bos, 2016) AMRs were transformed as HOL formulas modeling event semantics (Stabler, 2018) problems of quantification, negation were overcome . . .
Tree Adjoining Grammars (TAGs) (Joshi, Levy, and Takahashi, 1975)
◮ more expressive than context-free grammars (CFGs) ◮ (arguably) capable of modeling syntax of natural languages ◮ polynomial parsing algorithms (like CFGs) ◮ used for generation
2
SLIDE 7 Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
◮ semantic treebank ◮ de-languagized (still biased towards English) ◮ used for semantic parsing (Artzi, Lee, and Zettlemoyer, 2015) and generation (Flanigan
et al., 2016)
◮ limitations: (universal) quantification, negation ◮ recent developments:
AMRs were transformed as FOL formulas (Bos, 2016) AMRs were transformed as HOL formulas modeling event semantics (Stabler, 2018) problems of quantification, negation were overcome . . .
Tree Adjoining Grammars (TAGs) (Joshi, Levy, and Takahashi, 1975)
◮ more expressive than context-free grammars (CFGs) ◮ (arguably) capable of modeling syntax of natural languages ◮ polynomial parsing algorithms (like CFGs) ◮ used for generation
Abstract Categorial Grammars (ACGs) (De Groote, 2001)
◮ type-logical grammatical framework ◮ encodes grammatical formalisms, including TAG ◮ ACG encoding of TAG enjoys polynomial parsing and generation algorithms ◮ embodies Curry’s tecto/pheno level distinctions ◮ inspired by Montague’s translation from syntax to semantics (HOL formulas)
2
SLIDE 8 Motivation
Abstract Meaning Representation (AMR) (Banarescu et al., 2013)
◮ semantic treebank ◮ de-languagized (still biased towards English) ◮ used for semantic parsing (Artzi, Lee, and Zettlemoyer, 2015) and generation (Flanigan
et al., 2016)
◮ limitations: (universal) quantification, negation ◮ recent developments:
AMRs were transformed as FOL formulas (Bos, 2016) AMRs were transformed as HOL formulas modeling event semantics (Stabler, 2018) problems of quantification, negation were overcome . . .
Tree Adjoining Grammars (TAGs) (Joshi, Levy, and Takahashi, 1975)
◮ more expressive than context-free grammars (CFGs) ◮ (arguably) capable of modeling syntax of natural languages ◮ polynomial parsing algorithms (like CFGs) ◮ used for generation
Abstract Categorial Grammars (ACGs) (De Groote, 2001)
◮ type-logical grammatical framework ◮ encodes grammatical formalisms, including TAG ◮ ACG encoding of TAG enjoys polynomial parsing and generation algorithms ◮ embodies Curry’s tecto/pheno level distinctions ◮ inspired by Montague’s translation from syntax to semantics (HOL formulas)
2
SLIDE 9 AMR
Based on frames Uniquely rooted directed acyclic graph (DAG) with labeled edges and nodes
◮ graph nodes encode entities and events (neo-Davidsonian) ◮ edges represent relations among entities, events, etc.
Capable of expressing various phenomena (e.g. coreference)
3
SLIDE 10 AMR
Based on frames Uniquely rooted directed acyclic graph (DAG) with labeled edges and nodes
◮ graph nodes encode entities and events (neo-Davidsonian) ◮ edges represent relations among entities, events, etc.
Capable of expressing various phenomena (e.g. coreference) Problem with expressing universal quantification in DAG (maybe Hilbert’s ǫ-terms?) Example A boy wants to go / All boys want to / The boy wants to go / . . .
- all have same AMR semantics:
(w/want01 : arg0(b/boy) : arg1(g/go01 : arg0 b)) – AMR in PENMAN notation ∃w∃g∃b (instance(w, want01) ∧ instance(g, w)∧ instance(b, boy) ∧ arg0(w, b) ∧ arg1(w, g) ∧ arg0(g, b)) – AMR in FOL notation
3
SLIDE 11 AMR
Based on frames Uniquely rooted directed acyclic graph (DAG) with labeled edges and nodes
◮ graph nodes encode entities and events (neo-Davidsonian) ◮ edges represent relations among entities, events, etc.
Capable of expressing various phenomena (e.g. coreference) Problem with expressing universal quantification in DAG (maybe Hilbert’s ǫ-terms?) Stabler (2018): AAMR
◮ transform AMR DAG into tree ◮ use tree transducers to obtain HOL formulas with events
Example A boy wants to go / All boys want to / The boy wants to go / . . .
- all have same AMR semantics:
(w/want01 : arg0(b/boy) : arg1(g/go01 : arg0 b)) – AMR in PENMAN notation ∃w∃g∃b (instance(w, want01) ∧ instance(g, w)∧ instance(b, boy) ∧ arg0(w, b) ∧ arg1(w, g) ∧ arg0(g, b)) – AMR in FOL notation most(boy.pl, λb∃w(walk01.pres(w)∧ : arg0(w, b))) – Stabler’s HOL encoding
3
SLIDE 12 AMR
Based on frames Uniquely rooted directed acyclic graph (DAG) with labeled edges and nodes
◮ graph nodes encode entities and events (neo-Davidsonian) ◮ edges represent relations among entities, events, etc.
Capable of expressing various phenomena (e.g. coreference) Problem with expressing universal quantification in DAG (maybe Hilbert’s ǫ-terms?) Stabler (2018): AAMR
◮ transform AMR DAG into tree ◮ use tree transducers to obtain HOL formulas with events ◮ drawback: coreference is lost
Example A boy wants to go / All boys want to / The boy wants to go / . . .
- all have same AMR semantics:
(w/want01 : arg0(b/boy) : arg1(g/go01 : arg0 b)) – AMR in PENMAN notation ∃w∃g∃b (instance(w, want01) ∧ instance(g, w)∧ instance(b, boy) ∧ arg0(w, b) ∧ arg1(w, g) ∧ arg0(g, b)) – AMR in FOL notation most(boy.pl, λb∃w(walk01.pres(w)∧ : arg0(w, b))) – Stabler’s HOL encoding
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SLIDE 13
Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees – Operations on trees – Generated structures –
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SLIDE 14 Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees –
◮ Initial trees: domain of locality
Operations on trees – Generated structures – Example
NP Fred VP Adv loudly VP∗ S NP ↓ VP V laughs
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SLIDE 15 Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees –
◮ Initial trees: domain of locality
Operations on trees – substitution Generated structures – Example
NP Fred VP Adv loudly VP∗ S NP ↓ VP V laughs
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SLIDE 16 Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees –
◮ Initial trees: domain of locality ◮ Auxiliary trees: recursion
Operations on trees – substitution Generated structures – Example
NP Fred VP Adv loudly VP∗ S NP ↓ VP V laughs
4
SLIDE 17 Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees –
◮ Initial trees: domain of locality ◮ Auxiliary trees: recursion
Operations on trees – substitution and adjunction Generated structures – Example
NP Fred VP Adv loudly VP∗ S NP ↓ VP V laughs
4
SLIDE 18 Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees –
◮ Initial trees: domain of locality ◮ Auxiliary trees: recursion
Operations on trees – substitution and adjunction Generated structures – derived trees. Example
NP Fred VP Adv loudly VP∗ S NP ↓ VP V laughs S NP Fred VP Adv loudly VP V laughs
4
SLIDE 19 Tree-Adjoining Grammar (TAG) (Joshi, Levy, and Takahashi, 1975)
Elementary trees –
◮ Initial trees: domain of locality ◮ Auxiliary trees: recursion
Operations on trees – substitution and adjunction Generated structures – derived trees. Their by-products : derivation trees Example
NP Fred VP Adv loudly VP∗ S NP ↓ VP V laughs S NP Fred VP Adv loudly VP V laughs
αlaughs βloudly αFred
2 1
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SLIDE 20
1 ACG
ACG definition
SLIDE 21
Abstract Categorial Grammar (ACG)
(De Groote, 2001)
Main Features ACGs are a grammatical framework
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SLIDE 22 Abstract Categorial Grammar (ACG)
(De Groote, 2001)
Main Features ACGs are a grammatical framework An ACG G generates two languages :
◮ The abstract language A(G) ◮ The object language O(G)
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SLIDE 23 Abstract Categorial Grammar (ACG)
(De Groote, 2001)
Main Features ACGs are a grammatical framework An ACG G generates two languages :
◮ The abstract language A(G) ◮ The object language O(G)
Abstract language : Admissible structures (parse structures, derivations) Object language : An interpretation of the abstract language
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SLIDE 24 Abstract Categorial Grammar (ACG)
(De Groote, 2001)
Main Features ACGs are a grammatical framework An ACG G generates two languages :
◮ The abstract language A(G) ◮ The object language O(G)
Abstract language : Admissible structures (parse structures, derivations) Object language : An interpretation of the abstract language Basic properties Modularity Both languages are of the same nature – sets of linear λ-terms
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SLIDE 25 Abstract Categorial Grammar (ACG)
(De Groote, 2001)
Main Features ACGs are a grammatical framework An ACG G generates two languages :
◮ The abstract language A(G) ◮ The object language O(G)
Abstract language : Admissible structures (parse structures, derivations) Object language : An interpretation of the abstract language Basic properties Modularity Both languages are of the same nature – sets of linear λ-terms : ACGs can be composed
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SLIDE 26 Abstract Categorial Grammar (ACG)
(De Groote, 2001)
Main Features ACGs are a grammatical framework An ACG G generates two languages :
◮ The abstract language A(G) ◮ The object language O(G)
Abstract language : Admissible structures (parse structures, derivations) Object language : An interpretation of the abstract language Basic properties Modularity Both languages are of the same nature – sets of linear λ-terms : ACGs can be composed Parsing 2nd order ACGs are reversible (Salvati, 2005; Kanazawa, 2007)
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SLIDE 27 ACG definition
Definition (ACG) An abstract categorial grammar (ACG) G is a quadruple Σ1, Σ2, L, s, where
1 Σ1 and Σ2 are higher-order linear signatures, called the abstract vocabulary and the
- bject vocabulary, respectively;
2 L : Σ1 −
→ Σ2 is a lexicon; L(λx.M) = λx.L(M) and L(M N) = L(M) L(N)
3 s is a type of the abstract vocabulary (either atomic or built upon the atomic types in
Σ1), called the distinguished type of the grammar.
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SLIDE 28 ACG definition
Definition (ACG) An abstract categorial grammar (ACG) G is a quadruple Σ1, Σ2, L, s, where
1 Σ1 and Σ2 are higher-order linear signatures, called the abstract vocabulary and the
- bject vocabulary, respectively;
2 L : Σ1 −
→ Σ2 is a lexicon; L(λx.M) = λx.L(M) and L(M N) = L(M) L(N)
3 s is a type of the abstract vocabulary (either atomic or built upon the atomic types in
Σ1), called the distinguished type of the grammar. The abstract language: A(G) = {M ∈ Λ(Σ1) | ⊢Σ1 M : s is derivable}
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SLIDE 29 ACG definition
Definition (ACG) An abstract categorial grammar (ACG) G is a quadruple Σ1, Σ2, L, s, where
1 Σ1 and Σ2 are higher-order linear signatures, called the abstract vocabulary and the
- bject vocabulary, respectively;
2 L : Σ1 −
→ Σ2 is a lexicon; L(λx.M) = λx.L(M) and L(M N) = L(M) L(N)
3 s is a type of the abstract vocabulary (either atomic or built upon the atomic types in
Σ1), called the distinguished type of the grammar. The abstract language: A(G) = {M ∈ Λ(Σ1) | ⊢Σ1 M : s is derivable} The object language: O(G) = {N ∈ Λ(Σ2) | ∃M ∈ A (G ) : N = L(M)}
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SLIDE 30 ACG definition
Definition (ACG) An abstract categorial grammar (ACG) G is a quadruple Σ1, Σ2, L, s, where
1 Σ1 and Σ2 are higher-order linear signatures, called the abstract vocabulary and the
- bject vocabulary, respectively;
2 L : Σ1 −
→ Σ2 is a lexicon; L(λx.M) = λx.L(M) and L(M N) = L(M) L(N)
3 s is a type of the abstract vocabulary (either atomic or built upon the atomic types in
Σ1), called the distinguished type of the grammar. The abstract language: A(G) = {M ∈ Λ(Σ1) | ⊢Σ1 M : s is derivable} The object language: O(G) = {N ∈ Λ(Σ2) | ∃M ∈ A (G ) : N = L(M)} Modularity: ACGs can be composed as lexicons are functions.
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SLIDE 31
TAG as ACGs
TAG derivation trees Λ(ΣTAG)
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SLIDE 32
TAG as ACGs
TAG derivation trees Λ(ΣTAG) Derived trees Λ(Σtrees)
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SLIDE 33
TAG as ACGs
TAG derivation trees Λ(ΣTAG) Derived trees Λ(Σtrees) Gderived trees
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SLIDE 34
TAG as ACGs
TAG derivation trees Λ(ΣTAG) Derived trees Λ(Σtrees) Gderived trees Strings Λ(Σstring)
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SLIDE 35
TAG as ACGs
TAG derivation trees Λ(ΣTAG) Derived trees Λ(Σtrees) Gderived trees Strings Λ(Σstring) Gyield
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SLIDE 36
TAG as ACGs + Montague semantics (Pogodalla, 2004a)
TAG derivation trees Λ(ΣTAG) Derived trees Λ(Σtrees) Gderived trees Strings Λ(Σstring) Gyield Logical formulas Λ(Σlogic) GTAG sem.
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SLIDE 37
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees
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SLIDE 38
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees NP Fred
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SLIDE 39
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees CFred : NP NP1 Fred NP Fred
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SLIDE 40
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees CFred : NP NP1 Fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (S2 np (aV (VP2 (V1 laughs)))) NP Fred S NP↓ VP V laughs
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SLIDE 41
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees CFred : NP NP1 Fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (S2 np (aV (VP2 (V1 laughs)))) Cloudly : VPA ⊸ VPA λaV x. aV (V2 x (Adv1 loudly)) NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
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SLIDE 42
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees CFred : NP NP1 Fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (S2 np (aV (VP2 (V1 laughs)))) Cloudly : VPA ⊸ VPA λaV x. aV (V2 x (Adv1 loudly)) IXA : XA λx.x NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
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SLIDE 43
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees CFred : NP NP1 Fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (S2 np (aV (VP2 (V1 laughs)))) Cloudly : VPA ⊸ VPA λaV x. aV (V2 x (Adv1 loudly)) IXA : XA λx.x NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
αlaughs αfred βloudly 1 2
M0 = Cleft IS (Cloudly IV) CFred
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SLIDE 44
From TAG derivation to TAG derived trees
Derivation trees Their interpretations as derived trees CFred : NP NP1 Fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (S2 np (aV (VP2 (V1 laughs)))) Cloudly : VPA ⊸ VPA λaV x. aV (V2 x (Adv1 loudly)) IXA : XA λx.x NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
αlaughs αfred βloudly 1 2
M0 = Cleft IS (Cloudly IV) CFred Gyield ◦ Gderived trees(M0) = Fred + loudly + laughs
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SLIDE 45
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar
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SLIDE 46
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar CFred : NP λP. P fred NP Fred
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SLIDE 47
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar CFred : NP λP. P fred NP Fred S NP↓ VP V laughs
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SLIDE 48
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar CFred : NP λP. P fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (np (aV (λx. smile x))) NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
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SLIDE 49
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar CFred : NP λP. P fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (np (aV (λx. smile x))) Cloudly : VPA ⊸ VPA λ aV. aV (λx. loud x)) NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
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SLIDE 50
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar CFred : NP λP. P fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (np (aV (λx. smile x))) Cloudly : VPA ⊸ VPA λ aV. aV (λx. loud x)) IXA : XA λx.x NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
αlaughs αfred βloudly 1 2
M0 = Claughs IS (Cloudly IV) CFred
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SLIDE 51
From TAG derivation to Montague Translations (Pogodalla, 2004b)
Derivation trees Interpretations into Montague Grammar CFred : NP λP. P fred Claughs : SA ⊸ VPA ⊸ NP ⊸ S λ aS aV np. aS (np (aV (λx. smile x))) Cloudly : VPA ⊸ VPA λ aV. aV (λx. loud x)) IXA : XA λx.x NP Fred S NP↓ VP V laughs VP VP∗ Adv loudly
αlaughs αfred βloudly 1 2
M0 = Claughs IS (Cloudly IV) CFred LLog(M0) = loud (smile fred)
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SLIDE 52
TAG derivation trees to HOL (Pogodalla, 2017)
Constants of ΣTAG Their interpretations by GTAG sem. Cfred : NP λP. P fred : (e → t) → t Cwoman : nA ⊸ NP λD.λq .D woman q Csmart : nA ⊸ nA λD. λn .λq . D (λ x. (smart x) ∧ (n x))q Cevery, Ceach : nA λ P Q . ∀ x. (P x) ⊃ (Q x) Csome, Ca : nA λ P Q . ∃ x. (P x) ∧ (Q x) Ckissed : SA ⊸ VPA ⊸ NP ⊸ NP ⊸ S λadvs advv sbj obj. advs (sbj (λx.(obj (advv(λy.kiss x y))))) IX : XA λx.x S t
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SLIDE 53
Continuations, event semantics, ACG
Previous approaches syntax-event semantics interface using ACG (Winter and Zwarts, 2011) – their grammar is not TAG; syntax-event semantic interface (Champollion, 2015):
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SLIDE 54 Continuations, event semantics, ACG
Previous approaches syntax-event semantics interface using ACG (Winter and Zwarts, 2011) – their grammar is not TAG; syntax-event semantic interface (Champollion, 2015):
◮ uses continuations: verbs are of type (v → t) → t ◮ negation scopes over existentially closed formula (¬∃w . . .) ◮ no distinction of arguments and adjuncts, e.g.
λx.go x VS λf .∃w.go(w) ∧ f (w)
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SLIDE 55 Continuations, event semantics, ACG
Previous approaches syntax-event semantics interface using ACG (Winter and Zwarts, 2011) – their grammar is not TAG; syntax-event semantic interface (Champollion, 2015):
◮ uses continuations: verbs are of type (v → t) → t ◮ negation scopes over existentially closed formula (¬∃w . . .) ◮ no distinction of arguments and adjuncts, e.g.
λx.go x VS λf .∃w.go(w) ∧ f (w)
Our approach use continuations, like (Champollion, 2015) negation scopes over event quantifier, like (Champollion, 2015) retain arguments within a lexical entry of a verb, like AMR (universal) quantification, like (Stabler, 2018)
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SLIDE 56
Interpretation as HOL formulas modeling event semantics: First try
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SLIDE 57
Interpretation as HOL formulas modeling event semantics: First try
everything should get a chance for a continuation but one has to know when to stop (close)
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SLIDE 58
Interpretation as HOL formulas modeling event semantics: First try
everything should get a chance for a continuation but one has to know when to stop (close) S := (v → t) → t T := t Closure := λP.P True : ((v → t) → t) → t Cjohn := λP. P john Cwalks := λadvs advv subj. advs (subj (advv(λx.λh.∃w. (walk w) ∧ (arg0 w x) ∧ (h w)))) Csmart := λD.λn.λq.λf .D(λxh.(n x h) ∧ (smart x))q f CnA
every
:= λp.λq.λf .∀x.(p x f ) ⊃ (q x f ) CnA⊸NP
woman
:= λD.D(λ x h.(woman x ∧ h x)) C SA⊸SA
certainly
:= λm. λV . m (λh.V (λv.(certainly v) ∧ (h v)) C VPA⊸VPA
fast
:= λm. λV . m (λx.λh.Vx(λv.(fast v) ∧ (h v))) C VPA
does not
:= λVxh.¬(V x h)
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SLIDE 59 First try: Results
(1) Every smart woman walks. M1 = Closure (Cwalks IS IVP (Cwoman (Csmart Cevery))) : T M1 := ∀x(woman x ∧ smart x ⊃ ∃w (walk w) ∧ (arg0 w x))
SLIDE 60 First try: Results
(1) Every smart woman walks. M1 = Closure (Cwalks IS IVP (Cwoman (Csmart Cevery))) : T (2) John does not walk. M2 = Closure (Cwalks IS Cdoes not Cjohn) : T M1 := ∀x(woman x ∧ smart x ⊃ ∃w (walk w) ∧ (arg0 w x))
¬∃w (walk w) ∧ (arg0 w john)
SLIDE 61 First try: Results
(1) Every smart woman walks. M1 = Closure (Cwalks IS IVP (Cwoman (Csmart Cevery))) : T (2) John does not walk. M2 = Closure (Cwalks IS Cdoes not Cjohn) : T (3) Every smart woman walks fast. M3 = Closure (CwalksIS(Cfast IVP)(Cwoman (Csmart Cevery))) : T M1 := ∀x(woman x ∧ smart x ⊃ ∃w (walk w) ∧ (arg0 w x))
¬∃w (walk w) ∧ (arg0 w john)
∀x(woman x ∧ smart x ∧ fast x ⊃ ∃w(walk w) ∧ (arg0 w x) ∧ (fast w))
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SLIDE 62 First try: Results
(1) Every smart woman walks. M1 = Closure (Cwalks IS IVP (Cwoman (Csmart Cevery))) : T (2) John does not walk. M2 = Closure (Cwalks IS Cdoes not Cjohn) : T (3) Every smart woman walks fast. M3 = Closure (CwalksIS(Cfast IVP)(Cwoman (Csmart Cevery))) : T (4) Certainly, every smart woman walks. M4 = Closure (Cwalks(Ccertainly IS)IVP(Cwoman (Csmart Cevery))) : T M1 := ∀x(woman x ∧ smart x ⊃ ∃w (walk w) ∧ (arg0 w x))
¬∃w (walk w) ∧ (arg0 w john)
∀x(woman x ∧ smart x ∧ fast x ⊃ ∃w(walk w) ∧ (arg0 w x) ∧ (fast w)) M4 := ∀x (woman x∧smart x ∧ certainly x ⊃ ∃w(walk w) ∧ (arg0 w x)∧(certainly w))
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SLIDE 63
Locating the problem
S := (v → t) → t T := t Closure := λP.P True : ((v → t) → t) → t Cjohn := λP. P john Cwalks := λadvs advv subj. advs (subj (advv(λx.λh.∃w. (walk w) ∧ (arg0 w x) ∧ (h w)))) Csmart := λD.λn.λq.λf .D(λxh.(n x h) ∧ (smart x))q f CnA
every
:= λp.λq.λf .∀x.(p x f ) ⊃ (q x f ) CnA⊸NP
woman
:= λD.D(λ x h.(woman x ∧ h x)) C SA⊸SA
certainly
:= λm. λV . m (λh.V (λv.(certainly v) ∧ (h v)) C VPA⊸VPA
fast
:= λm. λV . m (λx.λh.Vx(λv.(fast v) ∧ (h v))) C VPA
does not
:= λVxh.¬(V x h)
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SLIDE 64
Second try: No continuations for noun phrases
New interpretations Cjohn := λP. P john : (e → Ω) → Ω Cwalks := λadvs advv subj .advs (subj (advv(λx.λh.∃w. (walk w) ∧ (arg0 w x) ∧ (h w)))) Cwoman := λD.D(λ x.woman x) Cevery := λPQ.λh.∀x(Px ⊃ Qxh) : (e → t) → (e → Ω) → Ω Ca := λPQ.λh.∃x(Px ∧ Qxh) : (e → t) → (e → Ω) → Ω Csmart := λD.λn.λq.λf .D(λx.(n x ) ∧ (smart x))q f Ccertainly := λm. λV . m (λh.V (λv.(certainly v) ∧ (h v)) Cfast := λm. λV . m (λx.λh.Vx(λv.(fast v) ∧ (h v))) Cdoes not := λVxh.¬(V x h) Citisnotthecase := λS h.¬(S h) Where: Ω ≡def (v → t) → t
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SLIDE 65
Second try: No continuations for noun phrases
New interpretations Cjohn := λP. P john : (e → Ω) → Ω Cwalks := λadvs advv subj .advs (subj (advv(λx.λh.∃w. (walk w) ∧ (arg0 w x) ∧ (h w)))) Cwoman := λD.D(λ x.woman x) Cevery := λPQ.λh.∀x(Px ⊃ Qxh) : (e → t) → (e → Ω) → Ω Ca := λPQ.λh.∃x(Px ∧ Qxh) : (e → t) → (e → Ω) → Ω Csmart := λD.λn.λq.λf .D(λx.(n x ) ∧ (smart x))q f Ccertainly := λm. λV . m (λh.V (λv.(certainly v) ∧ (h v)) Cfast := λm. λV . m (λx.λh.Vx(λv.(fast v) ∧ (h v))) Cdoes not := λVxh.¬(V x h) Citisnotthecase := λS h.¬(S h) Where: Ω ≡def (v → t) → t M3 :=∀x(woman x ∧ smart x ⊃ ∃w(walk w) ∧ (arg0 w x) ∧ (fast w)) M4 :=∀x(woman x ∧ smart x ⊃ ∃w(walk w) ∧ (arg0 w x) ∧ (certainly w))
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SLIDE 66 Bonus: Coreference, Raising
Cwants : SA ⊸ VPA ⊸ NP ⊸ S′
A
Cto-sleep : S′
A ⊸ S
Cwants := λadvs advv subj.λPred.advs (subj(advv.λx h. ∃w((want w) ∧ (h w) ∧ (arg0 w x) ∧ Pred(λQ.Q x)(λr. Arg1 w r)) Cto-sleep := λcont.cont(λsubj.subj(λx.λf .∃u.(sleep u) ∧ (arg0 u x) ∧ (f u)) S′
A :=
(((e → Ω) → Ω) → Ω) → Ω (5) a. John wants to sleep. M5 = Closure(Cto-sleep (Cwants IS IVPCjohn)) : T ∃w(want w) ∧ (arg0 w john) ∧ (∃u(sleep u) ∧ (Arg1 w u) ∧ (arg0 u john)) b. Every boy wants to sleep. M6 = Closure(Cto-sleep (Cwants IS IVP(CboyCevery))) : T ∀x(boy x ⊃∃w(want w)∧(arg0 w x)∧(∃u.(sleep u)∧(Arg1 w u)∧(arg0 u x))) c. Every boy does not want to sleep. M7 = Closure(Cto-sleep (Cwants IS IVP(CboyCevery))) : T ∀x(boy x ⊃¬(∃w(want w)∧(arg0 w x)∧(∃u.(sleep u)∧(Arg1 w u)∧(arg0 u x))))
- nly one reading out of two
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SLIDE 67
Future Work and Conclusion
TAG deriva- tion trees Derived trees Strings Logical formulas HOL formulas for event semantics
Current approach
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SLIDE 68
Future Work and Conclusion
TAG deriva- tion trees Derived trees Strings Logical formulas HOL formulas for event semantics
Current approach TAG derivation trees to Stable’s HOL translation of AMRs using ACGs Coreference missing in AAMR An approach to NLG with HOL encodings of AMRs for free
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SLIDE 69
Future Work and Conclusion
TAG deriva- tion trees Derived trees Strings Logical formulas HOL formulas for event semantics
Current approach TAG derivation trees to Stable’s HOL translation of AMRs using ACGs Coreference missing in AAMR An approach to NLG with HOL encodings of AMRs for free Future work Encode more complex interaction of quantifiers and negation A large scale ACG Maintain reasonable bounds on parsing/generation complexity
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SLIDE 70
Thank You
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SLIDE 71 References I
Artzi, Yoav, Kenton Lee, and Luke Zettlemoyer (2015). “Broad-coverage CCG Semantic Parsing with AMR”. In: Proceedings of the 2015 Conference on Empirical Methods in Natural Language Processing. Lisbon, Portugal: Association for Computational Linguistics, pp. 1699–1710. doi: 10.18653/v1/D15-1198. url: http://www.aclweb.org/anthology/D15-1198. Banarescu, Laura et al. (2013). “Abstract Meaning Representation for Sembanking”. In: Proceedings of the 7th Linguistics Annotation Workshop & Interoperability with
- Discourse. Sofia, Bulgaria, pp. 178–186.
Bos, Johan (2016). “Expressive Power of Abstract Meaning Representations”. In: Computational Linguistics 42.3, pp. 527–535. doi: 10.1162/COLI\_a\_00257. eprint: https://doi.org/10.1162/COLI_a_00257. url: https://doi.org/10.1162/COLI_a_00257. Champollion, Lucas (2015). “The interaction of compositional semantics and event semantics”. In: Linguistics and Philosophy 38.1, pp. 31–66. issn: 1573-0549. doi: 10.1007/s10988-014-9162-8.
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SLIDE 72 References II
De Groote, Philippe (2001). “Towards Abstract Categorial Grammars”. In: Association for Computational Linguistics, 39th Annual Meeting and 10th Conference of the European Chapter, Proceedings of the Conference, pp. 148–155. acl: P01-1033. url: http://aclweb.org/anthology/P/P01/P01-1033. Flanigan, Jeffrey et al. (2016). “Generation from Abstract Meaning Representation using Tree Transducers”. In: Proceedings of the 2016 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language
- Technologies. San Diego, California: Association for Computational Linguistics,
- pp. 731–739. doi: 10.18653/v1/N16-1087. url:
http://www.aclweb.org/anthology/N16-1087. Joshi, Aravind K., Leon S. Levy, and Masako Takahashi (1975). “Tree Adjunct Grammars”. In: Journal of Computer and System Sciences 10.1, pp. 136–163. doi: 10.1016/S0022-0000(75)80019-5. Kanazawa, Makoto (2007). “Parsing and Generation as Datalog Queries”. In: Proceedings
- f the 45th Annual Meeting of the Association of Computational Linguistics (ACL).
Prague, Czech Republic: Association for Computational Linguistics, pp. 176–183. acl: P07-1023. url: http://www.aclweb.org/anthology/P07-1023.
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SLIDE 73 References III
Pogodalla, Sylvain (2004a). “Computing Semantic Representation: Towards ACG Abstract Terms as Derivation Trees”. In: Proceedings of TAG+7, pp. 64–71. url: http://hal.inria.fr/inria-00107768/PDF/A04-R-058.pdf. – (2004b). “Computing Semantic Representation: Towards ACG Abstract Terms as Derivation Trees”. In: Proceedings of the Seventh International Workshop on Tree Adjoining Grammar and Related Formalisms (TAG+7), pp. 64–71. – (2017). “A syntax-semantics interface for Tree-Adjoining Grammars through Abstract Categorial Grammars”. In: Journal of Language Modelling 5.3, pp. 527–605. doi: 10.15398/jlm.v5i3.193. url: https://hal.inria.fr/hal-01242154. Salvati, Sylvain (2005). “Probl` emes de filtrage et probl` emes d’analyse pour les grammaires cat´
- gorielles abstraites”. PhD thesis. Institut National Polytechnique de Lorraine. url:
http://www.labri.fr/perso/salvati/downloads/articles/these.pdf. Stabler, Edward (2018). “Reforming AMR”. In: Formal Grammar. Ed. by Annie Foret, Reinhard Muskens, and Sylvain Pogodalla. Springer Berlin Heidelberg, pp. 72–87. isbn: 978-3-662-56343-4. Winter, Yoad and Joost Zwarts (2011). “Event Semantics and Abstract Categorial Grammar”. In: The Mathematics of Language. Ed. by Makoto Kanazawa et al. Springer Berlin Heidelberg, pp. 174–191.
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