WordNet PropBank

NomBank

Nathan Schulte

WordNet – A lexical database for English

WordNet, PropBank, NomBank – Nathan Schulte

A lexical database

● Expresses nouns, verbs, adjectives, and adverbs as related groups● Each group is called a synset – “cognitive synonyms”● Synsets are interlinked via semantic and lexical relations● Creates a web-like network of words – WordNet

The project – WordNet ®

● Princeton University● Free (gratis), both research and commercial use

● Must accept license● Must provide proper citation

● Current release is version 3.0● Windows: version 2.1

WordNet – some data

WordNet, PropBank, NomBank – Nathan Schulte

The database/network

● Over 150000 unique words● Nearly 120000 synsets● Resulting in nearly 210000 captured word-senses

API bindings

● Microsoft .NET (C#), Java● Perl, PHP, Python, Ruby

● Python via NLTK Project● Prolog

Other interfaces● Many web interfaces and bindings – REST/RESTful● XML encodings● SQL adaptations● Many “viewer” applications

WordNet – relations

WordNet, PropBank, NomBank – Nathan Schulte

Synonyms - synsets

● e.g. big – large, buy – purchase, quickly – speedily● Primary relation in WordNet

Hypernyms / hyponyms - “forest” relation

● e.g. furniture → bed → bunkbed, scarlet → red → color● Primary relation among synsets● Distinguishes proper nouns from common nouns (“instances” from “types”)

Meronyms - whole/part relation● e.g. chair – set, leg, back

● Parts are inherited from their parent categories (“superordinates”)● Chair has legs, armchair also then has legs

● Relation is one way; superordinates do not inherit siblings' children● Chairs have legs, as do “kinds of chairs”, but “kinds of furniture” do no always have legs

WordNet – more relations; verbs, adjectives

WordNet, PropBank, NomBank – Nathan Schulte

Troponyms - “manner” relation

● e.g. communicate → talk → whisper● Verbs arranged into hierarchies of troponyms● Children of hierarchy are more troponymic; they express the manner of action in more detail

“Entails” relations

● e.g. buy → pay, succeed → try, show → see● entails: “events that necessarily and uni-directionally entail one another”

Antonyms

● e.g. wet – dry, young – old● “direct” opposites are annotated; “polar adjectives” only

Pertainyms - relational adjectives

● e.g. criminal → crime

PropBank – Semantic Proposition Bank

WordNet, PropBank, NomBank – Nathan Schulte

What is PropBank?

● Created a corpus with annotations about basic semantic propositions● Adds predicate-argument relations to the Penn Treebank syntax trees● University of Colorado at Boulder● Funded by ACE, continuation by NSF and DARPA

Wait... What is PropBank?

● Has a similar function as FrameNet – “frame”● Provides a database of framesets

● Each frameset frames a predicate● Each framesets contain rolesets

● roleset is essentially a specific sense of the verb of the frameset

PropBank – it's just data

WordNet, PropBank, NomBank – Nathan Schulte

Some background

● Frequently compared to FrameNet, but much simpler in basis● Originally intended as training data for machine learning-based SRL

● Focused on verbs; identifying their arguments● Each word sense of a verb equates to a roleset, but only if the difference affects the

arguments there-of; e.g.● amount.01 - “sums to”

● <role descr="thing(s) being counted" n="1"/>● <role descr="count, total" n="2"/>

● amount.02 - “is equivalent to”● <role descr="focus" n="1"/>● <role descr="ground, introduced by 'to'" n="2"/>

PropBank – an example: forego.xml

WordNet, PropBank, NomBank – Nathan Schulte

<!DOCTYPE frameset SYSTEM "frameset.dtd"><frameset><predicate lemma="forego">

<roleset id="forego.01" name="to abstain, refrain from, or do without" vncls=""> <roles> <role descr="abstainer" n="0"></role> <role descr="thing foregone" n="1"></role> </roles>

<example name="Angel Gabriel"> <text> What Garbriel was asking *T*-1 was that mankind forego all its parochial moral judgements. </text>

<arg n="0">mankind</arg> <rel>forego</rel> <arg n="1">all its parochial moral judgements</arg>

</example> </roleset>

<note>frame by Perryn</note> </predicate></frameset>

PropBank – it's still just data

WordNet, PropBank, NomBank – Nathan Schulte

How do I use it?

● Provided as a collection of XML files, each of which is a self-contained frameset● Other projects have converted PropBank into other data formats

● A combined set, the “Unified Verb Index” combines PropBank, FrameNet, and VerbNet● http://verbs.colorado.edu/verb-index/index.php

● The project also provides an HTML rendition of the original XML annotations● http://verbs.colorado.edu/propbank/framesets-english/

NomBank – Noun Annotation Bank

WordNet, PropBank, NomBank – Nathan Schulte

What is NomBank?

● NomBank – Nominal, noun, bank● Similar to PropBank, except for nouns, not verbs

● Looks at arguments of nouns in the corpus● “to mark the sets of arguments that cooccur with nouns just as PropBank records such

information for verbs”● New York University

● Based on a project called Nomlex

● Current release: version 1.0

NomBank – it's still just data

WordNet, PropBank, NomBank – Nathan Schulte

Three lexicons

● NOMLEX-PLUS● The whole of the NOMLEX project, with semi-automatically generated additions

● PropBank frame files● Same thing as PropBank, but for nouns● Contains relations from NomBank noun senses to PropBank verb senses

● Morhpology file● A single file, read one line at a time● Each line starts with a base form of a noun, and is followed by possible morphologic forms

NomBank – an example

WordNet, PropBank, NomBank – Nathan Schulte

<!DOCTYPE frameset SYSTEM "frameset.dtd"><frameset><predicate lemma="shard"> <roleset id="shard.01" name="partitive-part"> <roles> <role descr="whole" n="1"></role> </roles>

<example name="autogen1"> <text> shards of metal </text>

<rel>shards</rel> <arg n="1">of metal</arg> </example> </roleset></predicate></frameset>

NomBank – another example: shopping.xml

WordNet, PropBank, NomBank – Nathan Schulte

<!DOCTYPE frameset SYSTEM "frameset.dtd"><frameset><predicate lemma="shopping"> <roleset id="shopping.01" name="look for something to buy" source="verb-shop.01" vncls="35.2"> <roles> <role descr="shopper" n="0"> <vnrole vncls="35.2" vntheta="Agent"/></role> <role descr="thing sought" n="1"> <vnrole vncls="35.2" vntheta="Theme"/></role> <role descr="source" n="2"></role> <role descr="beneficiary" n="4"></role> </roles>

<example name="autogen1"> <text> one-stop shopping for takeover finance </text>

<arg n="2">one-stop</arg> <rel>shopping</rel> <arg n="1">for takeover finance</arg> </example> </roleset></predicate></frameset>

<!DOCTYPE frameset SYSTEM "frameset.dtd"><frameset><predicate lemma="shop"> <roleset id="shop.01" name="look for something to buy" vncls="35.2"> <roles> <role descr="shopper" n="0"> <vnrole vncls="35.2" vntheta="Agent"/></role> <role descr="thing sought" n="1"> <vnrole vncls="35.2" vntheta="Theme"/></role> <role descr="benefactive" n="4"/> </roles>

WordNet, PropBank, NomBank – Nathan Schulte

Projects are corpus based; PTB WSJ

Processes involved in projects are general...

...

Anything else...

References

WordNet, PropBank, NomBank – Nathan Schulte

WordNet - http://wordnet.princeton.edu/wordnet/

● http://en.wikipedia.org/wiki/Wordnet

PropBank - http://verbs.colorado.edu/~mpalmer/projects/ace.html● http://en.wikipedia.org/wiki/PropBank

● http://verbs.colorado.edu/propbank/

● http://en.wikipedia.org/wiki/VerbNet

● http://verbs.colorado.edu/verb-index/index.php

NomBank - http://nlp.cs.nyu.edu/meyers/NomBank.html

● http://nlp.cs.nyu.edu/meyers/nombank/nombank-specs-2007.pdf● http://nlp.cs.nyu.edu/nomlex/index.html