Fuzzy Semantic Grammar

Motivations :

• Easy to encode domain knowledge

• Strong to parse NL sentence

• Useful for speech recognition

Jiping Sun October 2003

Semantic Grammar Formalism

Jiping Sun October 2003

FSG = { (A) Lexicon : +(w) C, (B) Templates : T = C1 …Cj … Ck

(C) I.M.1 Rules : C {wk|wi…wj}(A), (B): expressing world knowledge in grammar.(B), (C): enabling speech recognition W.L.2 search. (C): generating natural language complexity.

1. I.M. = Information mass, 2. W.L. = word lattice

Example-1

Jiping Sun October 2003

Natural language sentence :

“A ship carrying more than seventy-five million

liters of oil sank November nineteenth in waters

near the coast of northwestern Spain.”(source: VOA ENVIRONMENT REPORT, Nov. 29, 2002)

Example-1

Jiping Sun October 2003

Template with lexeme :

[A ship]1 carrying more than seventy-five million

liters of oil [sank]2 November nineteenth in

waters [near the coast of northwestern Spain]3.

T = 1[Vehicle] + 2[Movement] + 3[Location]

Example-1

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Information-mass rules :

[vehicle] { ship | carry [substance] }

[substance] { oil | [quantity] of }

[quantity] { liter | [numerical] }

[A ship] carrying more than seventy-five million liters of oil

[sank] November nineteenth in waters [near the coast of

northwestern Spain].

Example-1

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Information-mass rules :

[movement] { sank | [time] }

[time] { [month] | [date] }

[location] { Spain | [direction] [geo_part] }

[geo-part] { coast | in waters, near the }

[A ship] carrying more than seventy-five million liters of oil

[sank] November nineteenth in waters [near the coast of

northwestern Spain].

Example-2

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Natural language sentence :

“The Bush administration has announced new

proposals designed to ease controls on

industrial pollution.”(source: VOA ENVIRONMENT REPORT, Dec. 13, 2002)

Example-2

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Template with lexeme :

The Bush [administration]1 has [announced]2

new [proposals]3 designed to ease [controls]4

on industrial pollution.

T = 1[Org] + 2[Issue] + 3[Doc] + 4[Purpose]

Example-2

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Information-mass rules :

[Org] { administration | [leader] }

[Issue] { announce | [modal_time] }

[Doc] { proposal | new }

The Bush [administration] has [announced] new [proposals]

designed to ease [controls] on industrial pollution .

Example-2

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Information-mass rules :

[doc] { proposal | gen::designed to }

[purpose] { control | on industrial pollution }

[purpose] { control | deg::ease }

The Bush [administration] has [announced] new [proposals]

designed to ease [controls] on industrial pollution .

World Knowledge & Language

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Templates encode core knowledge Categories are semantically defined

E.g.

Vehicle Move in-Time at-Location

Org Issue Doc to-Purpose

Pollution can-be controlled

World Knowledge & Language (2)

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I.M. rules expand core knowledge Constructs: specificity, auxiliary-ness …

E.g. IM(Spain)>IM(coast)>IM(water) | Location (spec) IM(control) > IM(ease) > IM(try) | purpose (auxi)

FSG for Speech Recognition

Jiping Sun October 2003

Word lattice re-scoring is important Templates search key word string I.M. rules search for other words This scheme can tolerate SR errors order of search :

A ship carrying more than seventy-five million liters of oil sank

November nineteenth in waters near the coast of northwestern

Spain

Fuzzy Natural Language Grammar

Jiping Sun October 2003

NL is a very flexible system Events can be rendered in arbitrary detail To deal with it, use fuzzy rules

Fuzzy lexicons: Fuzzy semantic templates:

Fuzzy information mass rules:

w C [0,1]

Ci Tj [0,1]

w | Ci (C ) [0,1]