Documentation

Linglib.Phenomena.FillerGap.Studies.HPSGExtraction

Bridge: HPSG Extraction to Filler-Gap Phenomena #

@cite{sag-wasow-bender-2003} @cite{hofmeister-sag-2010}

Connects HPSG's Head-Filler Schema and SLASH mechanism to empirical filler-gap data in Phenomena.FillerGap.

Main results #

object_extraction_licensed: HPSG correctly derives object wh-questions via gap introduction + SLASH amalgamation + Head-Filler discharge
island_blocks_extraction: GAP restrictions block SLASH propagation through island constructions
weak_island_np_ok: Weak islands allow NP extraction but block PP
extraction_and_island_complementary: extraction succeeds iff not blocked by an island

structure Phenomena.FillerGap.Studies.HPSGExtraction.ExtractionConfig :

Model of a filler-gap dependency: a wh-filler, a gapped clause, and an optional island restriction on the embedded domain.

fillerCat : UD.UPOS
Category of the filler (wh-phrase)
gapCat : UD.UPOS
Category of the gap (missing complement)
restriction : HPSG.GapRestriction
GAP restriction on intervening domain (if any)

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.extractionLicensed (cfg : ExtractionConfig) :

Is extraction licensed under HPSG?

The filler's category must be compatible with the gap
The SLASH value must survive any island restrictions

Equations

One or more equations did not get rendered due to their size.

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.objectWhQuestion :

ExtractionConfig

Object wh-question: "What did John see ___?" NP gap, NP filler, no island → licensed.

Equations

Phenomena.FillerGap.Studies.HPSGExtraction.objectWhQuestion = { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN }

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.subjectWhQuestion :

ExtractionConfig

Subject wh-question: "Who saw Mary?" In HPSG, subject questions don't need extraction — the wh-word IS the subject. But we can model it as NP gap + NP filler for uniformity.

Equations

Phenomena.FillerGap.Studies.HPSGExtraction.subjectWhQuestion = { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN }

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.whIslandExtraction :

ExtractionConfig

Extraction from an embedded question (wh-island): blocked. "*What did John wonder who saw ___?"

Equations

Phenomena.FillerGap.Studies.HPSGExtraction.whIslandExtraction = { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := HPSG.GapRestriction.noGap }

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.topicIslandExtraction :

ExtractionConfig

Extraction from a topicalized clause: blocked. "*What did this book, John read ___?"

Equations

Phenomena.FillerGap.Studies.HPSGExtraction.topicIslandExtraction = { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := HPSG.GapRestriction.noGap }

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.weakIslandNP :

ExtractionConfig

NP extraction from a weak island: allowed. "Which employee did Albert learn whether they dismissed ___?"

Equations

Phenomena.FillerGap.Studies.HPSGExtraction.weakIslandNP = { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := HPSG.GapRestriction.npOnly }

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.weakIslandPP :

ExtractionConfig

PP extraction from a weak island: blocked. "*In which city did you wonder whether John lives ___?"

Equations

Phenomena.FillerGap.Studies.HPSGExtraction.weakIslandPP = { fillerCat := UD.UPOS.ADP, gapCat := UD.UPOS.ADP, restriction := HPSG.GapRestriction.npOnly }

Instances For

def Phenomena.FillerGap.Studies.HPSGExtraction.islandToGapRestriction :

ConstraintType → HPSG.GapRestriction

Map island constraint types to HPSG GAP restrictions.

This is the key connection: empirical island classifications map to specific GAP feature values in HPSG.

Equations

Instances For

theorem Phenomena.FillerGap.Studies.HPSGExtraction.absolute_islands_block :

have cnpc := { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := islandToGapRestriction ConstraintType.complexNP }; have adj := { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := islandToGapRestriction ConstraintType.adjunct }; have coord := { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := islandToGapRestriction ConstraintType.coordinate }; extractionLicensed cnpc = false ∧ extractionLicensed adj = false ∧ extractionLicensed coord = false

HPSG predicts all absolute islands block extraction.

theorem Phenomena.FillerGap.Studies.HPSGExtraction.gap_removes_complement :

have see_ss := { cat := UD.UPOS.VERB, val := { subj := [UD.UPOS.NOUN ], comps := [UD.UPOS.NOUN ] } }; have see_w := { form := "see", cat := UD.UPOS.VERB }; Option.map (fun (p : HPSG.Sign × HPSG.SlashValue) => p.fst.synsem.val.comps.isEmpty && p.snd.gaps == [UD.UPOS.NOUN ]) (HPSG.gapComplement see_w see_ss 0) = some true

The gap introduction mechanism correctly removes complements.

theorem Phenomena.FillerGap.Studies.HPSGExtraction.extraction_and_island_complementary :

have free := { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN }; have abs := { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := HPSG.GapRestriction.noGap }; have weakNP := { fillerCat := UD.UPOS.PRON, gapCat := UD.UPOS.NOUN, restriction := HPSG.GapRestriction.npOnly }; have weakPP := { fillerCat := UD.UPOS.ADP, gapCat := UD.UPOS.ADP, restriction := HPSG.GapRestriction.npOnly }; extractionLicensed free = true ∧ extractionLicensed abs = false ∧ extractionLicensed weakNP = true ∧ extractionLicensed weakPP = false

End-to-end: extraction is licensed iff not blocked by an island.