Weighted parsing for grammar-based language models FSMNLP 2019 - - PowerPoint PPT Presentation
Weighted parsing for grammar-based language models FSMNLP 2019 - - PowerPoint PPT Presentation
Weighted parsing for grammar-based language models FSMNLP 2019 Richard Mrbitz Heiko Vogler 2019-09-25 The weighted parsing problem language e.g., English sentences ( ) syntactic object e.g., Fruit fmies like bananas ?
The weighted parsing problem
language
e.g., English sentences (β π¦β)
syntactic object
e.g., Fruit fmies like bananas
β ?
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 2 / 21
The weighted parsing problem
language
e.g., English sentences (β π¦β)
syntactic object
e.g., Fruit fmies like bananas
β ? language model
e.g., context-free grammar (CFG)
structural representations
e.g., abstract syntax trees (ASTs)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 2 / 21
The weighted parsing problem
language
e.g., English sentences (β π¦β)
syntactic object
e.g., Fruit fmies like bananas
β ? language model
e.g., context-free grammar (CFG)
structural representations
e.g., abstract syntax trees (ASTs)
value in a weight algebra
(Goodman 1999; Nederhof 2003)
parse
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 2 / 21
Overview
Semiring parsing
(Goodman 1999)
Weighted deductive parsing
(Nederhof 2003)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 21
Overview
Semiring parsing
(Goodman 1999)
Weighted deductive parsing
(Nederhof 2003)
Mohri (2002)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 21
Overview
Semiring parsing
(Goodman 1999)
Weighted deductive parsing
(Nederhof 2003)
Mohri (2002) Algebraic dynamic programming
(Giegerich, Meyer, and Stefgen 2004)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 21
Overview
Semiring parsing
(Goodman 1999)
Weighted deductive parsing
(Nederhof 2003)
Mohri (2002) Algebraic dynamic programming
(Giegerich, Meyer, and Stefgen 2004)
Our approach
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 21
Outline
1
Weighted RTG-based language models
2
The weighted parsing problem
3
The weighted parsing algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 4 / 21
Outline
1
Weighted RTG-based language models
2
The weighted parsing problem
3
The weighted parsing algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 5 / 21
Regular tree grammars (RTG)
Tuple π» = (π, π΅, π΅0, π) Example rules: S β π½(NP, VP) VP β πΎ(VBZ, PP) NP β πΏ(NN) NN β π β¦ S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦ abstract syntax tree π β AST(π»)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 6 / 21
Regular tree grammars (RTG)
Tuple π» = (π, π΅, π΅0, π) Example rules: S β π½(NP, VP) VP β πΎ(VBZ, PP) NP β πΏ(NN) NN β π β¦ S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦ abstract syntax tree π β AST(π»)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 6 / 21
Regular tree grammars (RTG)
Tuple π» = (π, π΅, π΅0, π) Example rules: S β π½(NP, VP) VP β πΎ(VBZ, PP) NP β πΏ(NN) NN β π β¦ S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦ abstract syntax tree π β AST(π») π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 6 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨Fruitβ©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨Fruitβ© β¨π¦1β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨Fruitβ© β¨π¦1β© β¨π¦1π¦2β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨Fruitβ© β¨π¦1β© β¨π¦1π¦2β© β¨π¦1 flies π¦2β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨Fruitβ© β¨π¦1β© β¨π¦1π¦2β© β¨π¦1 flies π¦2β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ Fruit πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨π¦1β© β¨π¦1π¦2β© β¨π¦1 flies π¦2β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ Fruit Fruit πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨π¦1π¦2β© β¨π¦1 flies π¦2β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ Fruit Fruit β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
β¨π¦1 flies π¦2β©
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
β¨Fruit flies β¦ β© Fruit Fruit β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
β¨Fruit flies β¦ β© Fruit Fruit β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Language algebras
interpretation of π΅ as operations on the set of syntactic objects β = π¦β (.)π¦β: Tπ΅ (terms) β π¦β (syntactic objects) factors(Fruit flies like bananas) = {Fruit, like bananas, β¦ } S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅: Tπ β Tπ΅
π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β: Tπ΅ β π¦β
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 7 / 21
Semirings
Algebraic structure (π, β, β, π, π) β is used to evaluate an AST to a weight β accumulates the weights of several ASTs Examples (πΊ, β¨, β§, false, true) the Boolean semiring with πΊ = {false, true} (ββ, +, β , 0, 1) the semiring of natural numbers (ββ, min, +, β, 0) the tropical semiring (β1
0, max, β , 0, 1) the Viterbi semiring
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 8 / 21
Semirings
Algebraic structure (π, β, β, π, π) β is used to evaluate an AST to a weight β accumulates the weights of several ASTs Examples (πΊ, β¨, β§, false, true) the Boolean semiring with πΊ = {false, true} (ββ, +, β , 0, 1) the semiring of natural numbers (ββ, min, +, β, 0) the tropical semiring (β1
0, max, β , 0, 1) the Viterbi semiring
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 8 / 21
Multioperator monoids (M-monoids)
Generalization of semirings (π, β, β, π, π) βΆ (π, β, π, π») binary β βΆ set of π-ary operations π» (here: distributive) Semiring (π, β, β, π, π) M-monoid (π, β, π, π»β) where π»β = {mul
(π) π
β£ π β π, π β β} mul
(π) π (π1, β¦ , ππ) = π β π1 β β― β ππ
Examples Viterbi M-monoid (β1
0, max, 0, π»mul)
Minimum edit distance M-monoid ({{π} β£ π β β}, min β βͺ, β , π»med) with π»med = {del, ins, rep=, repβ , nil}
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 9 / 21
Multioperator monoids (M-monoids)
Generalization of semirings (π, β, β, π, π) βΆ (π, β, π, π») binary β βΆ set of π-ary operations π» (here: distributive) Semiring (π, β, β, π, π) β M-monoid (π, β, π, π»β) where π»β = {mul
(π) π
β£ π β π, π β β} mul
(π) π (π1, β¦ , ππ) = π β π1 β β― β ππ
Examples Viterbi M-monoid (β1
0, max, 0, π»mul)
Minimum edit distance M-monoid ({{π} β£ π β β}, min β βͺ, β , π»med) with π»med = {del, ins, rep=, repβ , nil}
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 9 / 21
Multioperator monoids (M-monoids)
Generalization of semirings (π, β, β, π, π) βΆ (π, β, π, π») binary β βΆ set of π-ary operations π» (here: distributive) Semiring (π, β, β, π, π) β M-monoid (π, β, π, π»β) where π»β = {mul
(π) π
β£ π β π, π β β} mul
(π) π (π1, β¦ , ππ) = π β π1 β β― β ππ
Examples Viterbi M-monoid (β1
0, max, 0, π»mul)
Minimum edit distance M-monoid ({{π} β£ π β β}, min β βͺ, β , π»med) with π»med = {del, ins, rep=, repβ , nil}
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 9 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 1.0 0.6 β β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
0.12 β β¦ 0.2 1.0 0.6 β β¦
wt wt(π) β Tπ»
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weight algebras
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
Fruit flies β¦
(.)π¦β
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
wt: π (set of rules) β π» (set of operations)
(β1
0, max, 0, π»mul)
(.)β0
1: Tπ» (terms) β β1
0 (weight algebra)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 10 / 21
Weighted RTG-based language models
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
Defjnition (weighted RTG-based language model)
A wRTG-LM is a tuple ( (π» = (π, π΅, π΅0, π)) ββ β β β β β β β
RTG
, β β
language algebra
), (π, β, π, π») β
M-monoid
, wt β
wt: π β π»
).
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 11 / 21
Weighted RTG-based language models
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
Defjnition (weighted RTG-based language model)
A wRTG-LM is a tuple ( (π» = (π, π΅, π΅0, π)) ββ β β β β β β β
RTG
, β β
language algebra
), (π, β, π, π») β
M-monoid
, wt β
wt: π β π»
).
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 11 / 21
Outline
1
Weighted RTG-based language models
2
The weighted parsing problem
3
The weighted parsing algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 12 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
πβ² β AST(π») π’β² β Tπ΅
ππ΅ (.)π¦β
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
πβ² β AST(π») π’β² β Tπ΅
ππ΅ (.)π¦β
wt(πβ²) β Tπ»
wt
0.0144
(.)β1
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
πβ² β AST(π») π’β² β Tπ΅
ππ΅ (.)π¦β
wt(πβ²) β Tπ»
wt
0.0144
(.)β1
(β1
0, max, 0, π»mul)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
πβ² β AST(π») π’β² β Tπ΅
ππ΅ (.)π¦β
wt(πβ²) β Tπ»
wt
0.0144
(.)β1
(β1
0, max, 0, π»mul)
max {
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
πβ² β AST(π») π’β² β Tπ΅
ππ΅ (.)π¦β
wt(πβ²) β Tπ»
wt
0.0144
(.)β1
(β1
0, max, 0, π»mul)
max {
parse
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
S β π½(NP, VP) NP β πΏ(NN) NN β π VP β πΎ(VBZ, PP) β¦
π β AST(π»)
π½ πΏ π πΎ β¦
ππ΅ π’ β π(π») β Tπ΅
1.0 β π1 β π2 0.2 β π1 1.0 0.6 β π1 β π2 β¦
wt wt(π) β Tπ»
0.12 β β¦
(.)β1
Fruit flies β¦
(.)π¦β
πβ² β AST(π») π’β² β Tπ΅
ππ΅ (.)π¦β
wt(πβ²) β Tπ»
wt
0.0144
(.)β1
(β1
0, max, 0, π»mul)
max {
parse
parse(π) = ββ
πβAST(π»,π)
wt(π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 13 / 21
The weighted parsing problem
Examples Semiring parsing (Goodman 1999)
recognition string probability probability of best derivation derivation forest best derivation(s) π best derivation(s)
Parsing with superior grammars (Knuth 1977; Nederhof 2003) Algebraic dynamic programming (Giegerich, Meyer, and Stefgen 2004)
minimum edit distance matrix chain multiplication
Reduct of a grammar and a syntactic object (cf. Bar-Hillel, Perles, and Shamir 1961)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 14 / 21
Outline
1
Weighted RTG-based language models
2
The weighted parsing problem
3
The weighted parsing algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 15 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
?
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
? value computation algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
? value computation algorithm π(π΅β²
0)
=
?
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
? value computation algorithm π(π΅β²
0)
=
? weighted parsing algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 16 / 21
Canonical weighted deduction system
- wRTG-LM ((π», β), π, wt )
- π β β
wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
cwds
Parsing as deduction (Shieber, Schabes, and Pereira 1995) [π΅1 , π1] β¦ [π΅π , ππ] [π΅ , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 17 / 21
Canonical weighted deduction system
- wRTG-LM ((π», β), π, wt )
- π β β
wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
cwds
Parsing as deduction (Shieber, Schabes, and Pereira 1995) [π΅1 , π1] β¦ [π΅π , ππ] [π΅ , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 17 / 21
Canonical weighted deduction system
- wRTG-LM ((π», β), π, wt )
- π β β
wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
cwds
Parsing as deduction (Shieber, Schabes, and Pereira 1995) [π΅1 , π1] β¦ [π΅π , ππ] [π΅ , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 17 / 21
Canonical weighted deduction system
- wRTG-LM ((π», β), π, wt )
- π β β
wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
cwds
Parsing as deduction (Shieber, Schabes, and Pereira 1995) [π΅1 , π1] β¦ [π΅π , ππ] [π΅ , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 17 / 21
Canonical weighted deduction system
- wRTG-LM ((π», β), π, wt )
- π β β
wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
cwds
Parsing as deduction (Shieber, Schabes, and Pereira 1995) [π΅1 , π1] β¦ [π΅π , ππ] [π΅ , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 17 / 21
Canonical weighted deduction system
- wRTG-LM ((π», β), π, wt )
- π β β
wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
cwds
Parsing as deduction (Shieber, Schabes, and Pereira 1995) [π΅1 , π1] β¦ [π΅π , ππ] [π΅ , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 17 / 21
Weighted parsing algorithm
Two-phase pipeline (Goodman 1999; Nederhof 2003)
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) = ββ
πβAST(π»,π)
wt(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
? value computation algorithm π(π΅β²
0)
=
? weighted parsing algorithm
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 18 / 21
Value computation algorithm
Input: a wRTG-LM ((π»β², πβ± π£β ), (π, β, π, π»), wtβ² ) with π»β² = (πβ², π΅β², π΅β²
0, πβ²)
Variables: π: πβ² β π, πnew β π, changed β πΊ Output: π(π΅β²
0)
1: for each π΅ β πβ² do 2:
π(π΅) β π
3: repeat 4:
changed β false
5:
for each π΅ β πβ² do
6:
πnew β π
7:
for each π = (π΅ β β¨π¦1 β¦ π¦πβ©(π΅1, β¦ , π΅π)) in πβ² do
8:
πnew β πnew β wtβ²(π )(π(π΅1), β¦ , π(π΅π))
9:
if π(π΅) β πnew then
10:
changed β true
11:
π(π΅) β πnew
12: until changed = false
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 19 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
π2
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
π3
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
π4
β β β β β β β β π(A, S) B
π5
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( π π π ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( π1(π) β π2(π) π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.8 β 0 max 0.1 β 0 π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( π3() π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 π4(π2, π1) β π5() ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.7 β 0.5 β 0 max 0.1 ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) = ( π1 π2 π3 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( π1(π2) β π2(π3) π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.8 β 0.5 max 0.1 β 0.1 π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.4 π3() π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.4 0.5 π4(πβ²
2, πβ² 1) β π5()
) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.4 0.5 0.7 β 0.5 β 0.4 max 0.1 ) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.4 0.5 0.14 ) = ( πβ²
1
πβ²
2
πβ²
3
) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.4 0.5 0.14 ) β¦ β¦
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Value computation algorithm (example)
((π», πβ± π£β ), (π, π, β, π»), wt ) β ((π», πβ± π£β ), (β1
0, 0, max, π»mul), wt )
S
0.8β π1
β β β β β β β β πΏ(A) S
0.1β π1
β β β β β β β β π(B) A
0.5
β β β β β β β β π½ B
0.7β π1β π2
β β β β β β β β π(A, S) B
0.1
β β β β β β β β πΎ A B
π½ πΎ
S
πΏ π π
S A B ( ) β¦ ( 0.5 0.1 ) β¦ ( 0.4 0.5 0.14 ) β¦ ( 0.4 0.5 0.14 )
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 20 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
? value computation algorithm π(π΅0
β²)
=
?
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
? value computation algorithm π(π΅0
β²)
=
closed
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Goodman (1999)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
Termination and correctness
- wRTG-LM
((π», β), π, wt )
- π β β
parse(π) canonical weighted deduction system wRTG-LM ((π»β², πβ± π£β ), π, wtβ² )
ββ
πβAST(π»β²)
wtβ²(π)
=
value computation algorithm π(π΅0
β²)
=
closed weight preserving
Conditions
Suffjcient: ((π», β), π, wt ) is closed or nonlooping e.g., acyclic RTGs, superior M-monoids, algebraic dynamic programming β is fjnitely decomposable e.g., CFG, LCFRS, TAG
Goodman (1999) Nederhof (2003)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 21 / 21
References I
- Y. Bar-Hillel, M. Perles, and E. Shamir (1961). βOn Formal Properties of Simple
Phrase Structure Grammarsβ. Zeitschrift fΓΌr Phonetik, Sprachwissenschaft und
- Kommunikationsforschung. Reprinted in Y. Bar-Hillel. (1964). Language and
Information: Selected Essays on their Theory and Application, Addison-Wesley 1964, 116β150.
- R. Giegerich, C. Meyer, and P. Stefgen (2004). βA discipline of dynamic
programming over sequence dataβ. Science of Computer Programming.
- J. Goodman (1999). βSemiring Parsingβ. Computational Linguistics, 4.
- D. E. Knuth (1977). βA generalization of Dijkstraβs algorithmβ. Information
Processing Letters.
- M. Mohri (2002). βSemiring frameworks and algorithms for shortest-distance
problemsβ. Journal of Automata, Languages and Combinatorics. M.-J. Nederhof (2003). βSquibs and Discussions: Weighted deductive parsing and Knuthβs algorithmβ. Computational Linguistics.
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 1 / 5
References II
- S. Shieber, Y. Schabes, and F. Pereira (1995). βPrinciples and implementation of
deductive parsingβ. The Journal of Logic Programming.
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 2 / 5
Canonical weighted deduction system
wRTG-LM ((π», β), π, wt ) and π β β β wRTG-LM ((π»β², πβ± π£β ), π, wtβ² ) [π΅1 , π1 , π1] β¦ [π΅π , ππ , ππ] [π΅ , π , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) π΅1 β π1(β¦ ), β¦ , π΅π β ππ(β¦ ) are rules [π΅0, π, π] [π΅0, π] {π΅0 β π(β¦ ) is a rule Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 5
Canonical weighted deduction system
wRTG-LM ((π», β), π, wt ) and π β β β wRTG-LM ((π»β², πβ± π£β ), π, wtβ² ) [π΅1 , π1 , π1] β¦ [π΅π , ππ , ππ] [π΅ , π , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) π΅1 β π1(β¦ ), β¦ , π΅π β ππ(β¦ ) are rules [π΅0, π, π] [π΅0, π] {π΅0 β π(β¦ ) is a rule Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 5
Canonical weighted deduction system
wRTG-LM ((π», β), π, wt ) and π β β β wRTG-LM ((π»β², πβ± π£β ), π, wtβ² ) [π΅1 , π1 , π1] β¦ [π΅π , ππ , ππ] [π΅ , π , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) π΅1 β π1(β¦ ), β¦ , π΅π β ππ(β¦ ) are rules [π΅0, π, π] [π΅0, π] {π΅0 β π(β¦ ) is a rule Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 5
Canonical weighted deduction system
wRTG-LM ((π», β), π, wt ) and π β β β wRTG-LM ((π»β², πβ± π£β ), π, wtβ² ) [π΅1 , π1 , π1] β¦ [π΅π , ππ , ππ] [π΅ , π , π0] { π΅ β π(π΅1, β¦ , π΅π) is a rule π0, π1, β¦ , ππ β factors(π) π0 = π(π1, β¦ , ππ) π΅1 β π1(β¦ ), β¦ , π΅π β ππ(β¦ ) are rules [π΅0, π, π] [π΅0, π] {π΅0 β π(β¦ ) is a rule Weight preserving
1
Bijection π: AST(π», π) β AST(π»β²)
2
wt(π) = wtβ²(π(π)) for every π β AST(π», π)
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 3 / 5
Closed wRTG-LMs
cutout(π, π)
π 3 π 1 π 4 π 2 π 1 π 2 π 4 π 3 π 1 π 2 π 4 π 2 π 1 π 4 π 4 π 3 π 1 π 2 π 4 π 3 π 1 π 2 π 4 π 2 π 1 π 4 π 4 π 3 π 1 π 4 π 2 π 1 π 2 π 4 π 3 π 1 π 4 π 4 π 3 π 1 π 2 π 4 π 3 π 1 π 4 π 4
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 4 / 5
Closed wRTG-LMs
Defjnition
Let π β β. A wRTG-LM π£ = ((π», β), π, wt ) is π-closed if π is distributive and d-complete, and for each π β Tπ and cyclic string π β πβ the following holds: if there is a (π, π)-cyclic path in π, then wt(π)π β β¨
πβcutout(π,π)
wt(π)π = β¨
πβcutout(π,π)
wt(π)π . AST(π»)(π): each cycle at most π times closed, distributive, d-complete
Theorem
For every π β β and π-closed wRTG-LM ((π», β), π, wt ) the following holds:
ββ
πβAST(π»β²)
wt(π)π = β¨
πβAST(π»)(π)
wt(π)π .
Richard MΓΆrbitz, Heiko Vogler: Weighted parsing for grammar-based language models (FSMNLP 2019) 2019-09-25 5 / 5