Lexicalized Tree-Adjoining Grammars (LTAG) - ad-teaching.infor...
Lexicalized Tree-Adjoining Grammars (LTAG) - ad-teaching.infor... Lexicalized Tree-Adjoining Grammars (LTAG) - ad-teaching.infor...
Substitution Example (Substitution) S NP N Mary NP↓ VP V NP↓ saw S D a NP D↓ N cat NP VP N V NP Mary saw D N a cat 20 / 52
Adjunction Definition (Adjunction) Let γ be a tree containing an internal node n labeled by X and β an auxiliary tree whose root node is also labeled by X. By applying the adjunction operation on (γ, n) and β, one gets a copy γ ′ of γ in which β has taken the place of the subtree t rooted by n and t has been attached to the foot node of β. If γ, n, β do not fulfill the above conditions, the operation is undefined. S X X S X ∗ γ β γ ′ X X ∗ 21 / 52
- Page 1 and 2: Lexicalized Tree-Adjoining Grammars
- Page 3 and 4: Context-Free Grammars Definition (C
- Page 5 and 6: Tree-Substitution Grammars Example
- Page 7 and 8: Outline 1 Why CFGs are not enough (
- Page 9 and 10: Cross-Serial Dependencies Example (
- Page 11 and 12: Lexicalization Example (Lexicalized
- Page 13 and 14: Lexicalization Example (CFG which i
- Page 15 and 16: Outline 1 Why CFGs are not enough (
- Page 17 and 18: Initial Trees Definition (Initial T
- Page 19: Substitution Definition (Substituti
- Page 23 and 24: Adjunction Constraints Given TAG G
- Page 25 and 26: Lexicalization Example (strong lexi
- Page 27 and 28: Further Formal Properties of TAL Tr
- Page 29 and 30: TAG Parsing Parser: Given a string
- Page 31 and 32: Recognizing Adjunction But the algo
- Page 33 and 34: Dotted Tree We introduce the notion
- Page 35 and 36: Chart Items The algorithm stores in
- Page 37 and 38: Scan Operations Input string: c 1
- Page 39 and 40: Complete Operations 1 2 3 [γ, adr,
- Page 41 and 42: Recognizer Algorithm Algorithm (Rec
- Page 43 and 44: Complexity of Recognizer Given: n:
- Page 45 and 46: Recognizing Substitution Recognizer
- Page 47 and 48: LTAG-Spinal Parser LTAG-spinal: Rou
- Page 49 and 50: LTAG-Spinal Parser Graphical repres
- Page 51 and 52: Conclusion TAG: a grammar formalism
Adjunction<br />
Definition (Adjunction)<br />
Let γ be a tree containing an internal node n labeled by X and<br />
β an auxiliary tree whose root node is also labeled by X.<br />
By applying the <strong>ad</strong>junction operation on (γ, n) and β, one gets a<br />
copy γ ′ of γ in which β has taken the place of the subtree t rooted<br />
by n and t has been attached to the foot node of β. If γ, n, β do<br />
not fulfill the above conditions, the operation is undefined.<br />
S<br />
X<br />
X<br />
S<br />
X<br />
∗<br />
γ β<br />
γ ′<br />
X<br />
X ∗ 21 / 52
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