Documentation

Linglib.Discourse.Centering.Pronominalization

Centering Theory — The Pronominalization Constraint #

[GJW95] [GGG93] [PSDEH04]

Two variants of the constraint on realizing the backward-looking center: PronominalizationConstraint ("Rule 1" of [GJW95]) fires only when some pronoun is used; CbPronominalized ([GGG93]'s unconditional strengthening, motivated by the repeated-name penalty) is its consequent and so implies it.

source
def Discourse.Centering.CbPronominalized {E : Type u_1} {R : Type u_2} {U : Type u_3} [CfRankerOf E R] [Realizes U E] [Pronominalizes U E] (prev : Utterance E R) (cur : U) :
Prop

The backward-looking center of cur (after prev), if defined, is realized by a pronoun — [GGG93]'s unconditional strengthening of "Rule 1", motivated by the repeated-name penalty.

Equations
Instances For
    source
    @[instance_reducible]
    instance Discourse.Centering.CbPronominalized.decidable {E : Type u_1} {R : Type u_2} {U : Type u_3} [CfRankerOf E R] [Realizes U E] [Pronominalizes U E] (prev : Utterance E R) (cur : U) :
    Decidable (CbPronominalized prev cur)
    Equations
    source
    def Discourse.Centering.PronominalizationConstraint {E : Type u_1} {R : Type u_2} {U : Type u_3} [CfRankerOf E R] [Realizes U E] [Pronominalizes U E] (prev : Utterance E R) (cur : U) :
    Prop

    The pronominalization constraint — "Rule 1" of [GJW95]: if any element of Cf(prev) is pronominalized in cur, then the backward-looking center is pronominalized too. Vacuously satisfied when no pronoun is used.

    Equations
    Instances For
      source
      @[instance_reducible]
      instance Discourse.Centering.PronominalizationConstraint.decidable {E : Type u_1} {R : Type u_2} {U : Type u_3} [CfRankerOf E R] [Realizes U E] [Pronominalizes U E] (prev : Utterance E R) (cur : U) :
      Decidable (PronominalizationConstraint prev cur)
      Equations
      source
      theorem Discourse.Centering.CbPronominalized.constraint {E : Type u_1} {R : Type u_2} {U : Type u_3} [CfRankerOf E R] [Realizes U E] [Pronominalizes U E] {prev : Utterance E R} {cur : U} (h : CbPronominalized prev cur) :
      PronominalizationConstraint prev cur

      The unconditional constraint implies the conditional one, by construction: CbPronominalized is PronominalizationConstraint's consequent.