1. Lecture 19 Word Meanings II
CSCE Natural Language Processing
Lecture 19 Word Meanings II
Topics
Description Logic III
Overview of Meaning
Readings:
Text Chapter 189NLTK book Chapter 10
March 27, 2013

2. Overview Readings: Text 19 NLTK Book: Chapters 9 and 10
Last Time (Programming)
Wordnet overview
Today
Computational Semantics
Feature based grammars
Readings:
Text 19
NLTK Book: Chapters 9 and 10
Next Time: Computational Lexical Semantics

3. HW review Dropboxes Soon to exist: NER for handbook
frequency distribution - Handbook Assignment
Regular Expression /urllib2 - Identify prerequisites Assignment
Extend backoff tagger to include trigram Assignment
Test1

4. Wordnet
Most synsets are connected to other synsets via a number of semantic relations. These relations vary based on the type of word, and include:
Nouns
hypernyms: Y is a hypernym of X if every X is a (kind of) Y (canine is a hypernym of dog) “superordinate” “superclass”
hyponyms: Y is a hyponym of X if every Y is a (kind of) X (dog is a hyponym of canine) “IS-A”
coordinate terms: Y is a coordinate term of X if X and Y share a hypernym (wolf is a coordinate term of dog, and dog is a coordinate term of wolf) “sibling”
holonym: Y is a holonym of X if X is a part of Y (building is a holonym of window) “HAS-PART”
meronym: Y is a meronym of X if Y is a part of X (window is a meronym of building) “IS-PART” “IS-MEMBER”

5. Verbs Adjectives Adverbs
hypernym: the verb Y is a hypernym of the verb X if the activity X is a (kind of) Y (to perceive is an hypernym of to listen)
troponym: the verb Y is a troponym of the verb X if the activity Y is doing X in some manner (to lisp is a troponym of to talk)
entailment: the verb Y is entailed by X if by doing X you must be doing Y (to sleep is entailed by to snore)
coordinate terms: those verbs sharing a common hypernym (to lisp and to yell)
Adjectives
related nouns
similar to
participle of verb
Adverbs
root adjectives

6. x

7. Wordnet online Fig 19-1

8. Word senses A word sense is a distinct meaning
Synonym sets are relations among word senses
couch/sofa, car/automobile
antonyms also
long/short, big/large, rise/fall
extremes; or opposite in direction

9. Fig 19-2 Noun relations in wordnet

10. Fig 19-3 Verb relations in wordnet

11. Fig19-4-like IS-A (hyponym) Chain for lemma bass#7

12. Sister terms (= coordinate terms)

13. Thematic Roles 19.19 “Sasha broke the window.”
exists e,x,y breaking(e) & breaker(e, Sasha) & brokenThing(e, y) & window(y)
19.20 Pat opened the door.
Deep or thematic roles
Panini (Indian grammarian) circa 7th-4th century BC
Fillmore 1968, Gruber 1965

14. Fig 19.5 Common Thematic Roles

15. 19.6 Examples of Thematic Roles

16. Variations of expression
John broke the window.
John broke the window with a rock.
The rock broke the window.
The window broke.
The window was broken by John.

17. Case Frames for verbs Break Agent: Subject, Theme:Object
Agent: Subject, Theme:Object, Instrument: PP-with
Instrument:Subject, Theme:Object
Theme: Subject

18. 19.4.3 Problems with Thematic Roles
Example 19.27
the cook opened the jar with the new gadget.
the new gadget opened the jar.
Example 19.28
Shelly ate the banana with a fork.
*The fork ate the banana.

19. Prop Bank
PropBank is a corpus that is annotated with verbal propositions and their arguments—a "proposition bank".

20. PropBank Online

21. FrameNet

22. Framenet Core Roles

23. FrameNet Examples
... [Cook the boys] ... GRILL [Food their catches] [Heating_instrument on an open fire]. [Avenger I] 'll GET EVEN [Offender with you] [Injury for this]! [ Punishment This attack was conducted] [Support in] RETALIATION [ Injury for the U.S. bombing raid on Tripoli... [Sleeper They] [Copula were] ASLEEP [Duration for hours]

24. FrameNet Index of Lexical Units

25. Selectional restrictions of roles from PropBank

26. Fig 19-7 Hamburger Edible?

29. Figure 19.8 Shank’s Conceptual Dependencies
Roger Schank 1969  Professor at Yale
aclweb.org/anthology-new/C/C69/C pdf

30. Conceptual Dependency
Governing Categories
PP – an actor or object corresponds to concrete nominal nouns
ACT – an action
LOC – a location of a conceptualization
T – time of a conceptualization
Assisting Categories
PA – attribute of a PP
AA – attribute of an ACT
Graphical representation
aclweb.org/anthology-new/C/C69/C pdf

31. Conceptual syntax rules
Ref: ??? Elaine Rich’s Text on AI

32. CD Examples John ran. John is tall. John is a doctor. A nice boy.
John’s dog
John pushed the cart
John took the book from Mary
John drank milk
john fertilized the field
the plants grew
Bill shot Bob

33. CD for “John at the egg.” .

34. CD “John prevented Mary from giving the book to Bill.”
.More tenses and modes
p past
f future
t transition
k continuing
c conditional
/ negative
? Interrogative
pil present

35. Restaurant Script Roger Schank again
Collection of scenes describing typical events
e.g. “visit a restaurant”
Entering
Ordering
Eating
Paying/Leaving

36. Modifiers