GR-Based Improved Parse Selection

Sriwantha Sri Aravinda Attanayake

University of Cambridge

Grammar Relations (GR)

John saw a cat with a telescope

Subject

Indirect Object

Determiner

Grammar Relations (GR)

<GR List>(ncsubj saw John )(iobj saw with )(dobj saw cat )(dobj with telescope )(det telescope a )(det cat a )

John saw a cat with a telescope

Luckily…

Parser

<GR List>(ncsubj saw John )(iobj saw with )(dobj saw cat )(dobj with telescope )(det telescope a )(det cat a )

Re RankingChoice 1(|ncsubj| |saw| |John| _)(|iobj| |saw| |with|)(|dobj| |saw| |cat|)(|dobj| |with| |telescope|)(|det| |telescope| |a|)(|det| |cat| |a|)

Choice 2(|ncsubj| |saw| |John| _)(|dobj| |saw| |cat|)(|det| |cat| |a|)(|ncmod| _ |cat| |with|)(|dobj| |with| |telescope|)(|det| |telescope| )

Choice 3(|ncsubj| |saw| |John| _)(|ncmod| _ |saw| |with|)(|dobj| |with| |telescope|)(|det| |telescope| |a|)(|dobj| |saw| |cat|)

John saw a cat with a telescope

a cat a + catNP DT+ NN

John saw a cat with a telescope

Saw + with : 80% cat + with : 40%

100 million wordBritish National Corpus

(BNC)

Parse1(|ncsubj| |saw| |John| _)(|iobj| |saw| |with|)(|dobj| |saw| |cat|)(|dobj| |with| |telescope|)(|det| |telescope| |a|)(|det| |cat| |a|)

Parse 2(|ncsubj| |saw| |John| _)(|dobj| |saw| |cat|)(|det| |cat| |a|)(|ncmod| |cat| |with|)(|dobj| |with| |telescope|)(|det| |telescope| |a| )

Parse 3(|ncsubj| |saw| |John| _)(|ncmod| _ |saw| |with|)(|dobj| |with| |telescope|)(|det| |telescope| |a|)(|dobj| |saw| |cat|)

Count=1000

Count=5000

2000

F-Score

(ncsubj saw John )(iobj saw with )(dobj saw cat )

(ncsubj saw John )

(ncsubj saw John )(iobj saw with )(dobj saw cat )(dobj with telescope)(det telescope a )(det cat a )

100% accurate, Poor recall

100% recall, Poor accuracy

Current Progress

F Score Improvement 1%MRR (10 Parses) about 6%

Challenges

(dobj saw cat ) Count=0(dobj saw dog) Count=0(dobj saw it) Count=3

(dobj saw {any word}) Count=45(dobj of and) Count=170,203

Score= Average (Count)

EndProduction of ssauba2@cam.ac.uk