Current Research
William J. Rapaport
http://www.cse.buffalo.edu/~rapaport
CVA Research Group
SNePS Research Group (SNeRG)
Center for Cognitive Science
Cognitive Science
=def interdisciplinary study of mind/cognition
– (AI, PHI, PSY, LIN, etc.)
• Artificial Intelligence
(“good old-fashioned classical symbolic AI”)
– Computational philosophy
– Knowledge representation for natural-language
understanding
• Computational linguistics
• Knowledge representation and reasoning
Computational Philosophy
• Philosophy as source of computational problems;
computational solutions to philosophical problems
• Understanding understanding:
Syntax suffices for semantics
– How a computational cognitive agent can pass a Turing Test
• E.g., SNePS/Cassie
– & overcome the Chinese-Room-Argument objections to
the Turing Test
• It’s possible to pass TT without really thinking
Knowledge Representation for
Natural-Language Understanding
• Computational contextual vocabulary acquisition
(CVA)
– Based on Karen Ehrlich’s 1995 CS PhD dissertation
– $$ from:NSF ROLE Program
• Research On Learning and Education
• In STEM
– Science, Technology, Engineering, and Mathematics
– Formerly known as “SMET” 
– Joint research with Michael Kibby, GSE/LAI
CVA: From algorithm to curriculum
• People do “incidental” CVA:
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–
–
–
Know more words than explicitly taught
Learn the meanings of most words from context
Unconsciously
How?
CVA: From Algorithm to Curriculum (continued)
• People do “deliberate” CVA
–
–
–
–
–
–
You’re reading;
You understand everything you read, until…
You come across a new word
Not in dictionary
No one to ask
So, you try to figure out its meaning
from context + background knowledge
– How?
What does ‘brachet’ mean?
(From Malory’s Morte D’Arthur [page # in brackets])
1. There came a white hart running into the hall with
a white brachet next to him, and thirty couples
of black hounds came running after them. [66]
2. As the hart went by the sideboard, the white
brachet bit him. [66]
3. The knight arose, took up the brachet and rode
away with the brachet. [66]
4. A lady came in and cried aloud to King Arthur,
“Sire, the brachet is mine”. [66]
10. There was the white brachet which bayed at
him fast. [72]
18. The hart lay dead; a brachet was biting on his
throat, and other hounds came behind. [86]
CVA: From algorithm… (continued)
• CVA studied by computational linguists
– word-sense disambiguation
• Given ambiguous word and list of all meanings,
determine the correct meaning
• Multiple-choice test 
– CVA as we do it:
• Given new word, compute its meaning
• Essay question 
Implementation
• SNePS (Stuart C. Shapiro & SNeRG):
– Intensional, propositional semantic-network
knowledge-representation & reasoning system
– Node-based & path-based reasoning
• I.e., logical inference & generalized inheritance
– SNeBR belief revision system
• Used for revision of definitions
– SNaLPS natural-language input/output
– “Cassie”: computational cognitive agent
How It Works
• SNePS represents:
– background knowledge + text information
in a single, consolidated semantic network
• Algorithms search network for slot-fillers
for definition frame
• Search is guided by desired slots
– E.g., prefers general info over particular info,
but takes what it can get
Cassie learns what “brachet” means:
Background info about: harts, animals, King Arthur, etc.
No info about:
brachets
Input:
formal-language version of simplified English
A hart runs into King Arthur’s hall.
• In the story, B17 is a hart.
• In the story, B18 is a hall.
• In the story, B18 is King Arthur’s.
• In the story, B17 runs into B18.
A white brachet is next to the hart.
• In the story, B19 is a brachet.
• In the story, B19 has the property “white”.
• Therefore, brachets are physical objects.
(deduced while reading;
Cassie believes that only physical objects have color)
--> (defineNoun "brachet")
Definition of brachet:
Class Inclusions:
phys obj,
Possible Properties: white,
Possibly Similar Items:
animal, mammal, deer,
horse, pony, dog,
I.e., a brachet is a physical object that can be white
and that might be like an animal, mammal, deer,
horse, pony, or dog
A hart runs into King Arthur’s hall.
A white brachet is next to the hart.
The brachet bites the hart’s buttock.
The knight picks up the brachet.
The knight carries the brachet.
--> (defineNoun "brachet")
Definition of brachet:
Class Inclusions: animal,
Possible Actions: bite buttock,
Possible Properties: small, white,
Possibly Similar Items: mammal, pony,
A hart runs into King Arthur’s hall.
A white brachet is next to the hart.
The brachet bites the hart’s buttock.
The knight picks up the brachet.
The knight carries the brachet.
The lady says that she wants the brachet.
The brachet bays at Sir Tor.
[background knowledge: only hunting dogs bay]
--> (defineNoun "brachet")
Definition of brachet:
Class Inclusions: hound, dog,
Possible Actions: bite buttock, bay, hunt,
Possible Properties: valuable, small, white,
I.e. A brachet is a hound (a kind of dog) that can bite, bay, and hunt,
and that may be valuable, small, and white.
General Comments
• System’s behavior  human protocols
• System’s definition  OED’s definition:
= A brachet is “a kind of hound which hunts by scent”
• Our inferential search algorithms are
“syntactic semantics” in action
CVA: … to curriculum
•
Is this an algorithm? (Clarke & Nation 1980):
1. Look at word & context
a) determine POS
2. Look at grammatical context
a) who does what to whom?
3. Look at wider context
a) Search for spatial/temporal/classification cues…
4. Guess the word; check your guess
CVA: From Algorithm to Curriculum
•
“guess the word”
=
“then a miracle
occurs”
• Surely we computer
scientists can
“be more explicit”!
CVA: From algorithm to curriculum … and back again!
• Treat “guess” as a procedure call
– Fill in the details with our algorithm
– Convert the algorithm into a curriculum
• To enhance students’ abilities to use deliberate CVA strategies
– To improve reading comprehension of STEM texts
• And use knowledge gained from CVA case studies
to improve the algorithm
• I.e., use Cassie to learn how to teach humans
& use humans to learn how to teach Cassie
Meetings & Websites
• SNeRG:
−Fridays, 9:00-11:00, Bell 242
 starting Aug. 29 (tomorrow)
 www.cse.buffalo.edu/sneps
• Center for Cognitive Science:
−Wednesdays, 2:00-4:00, Park 280
 starting Sept. 3
 wings.buffalo.edu/cogsci
• CVA:
−Mondays, 2:00-3:30, Baldy 17
 starting Sept. 8
 www.cse.buffalo.edu/~rapaport/cva.html
Courses
• Fall 2003:
– CSE 663: Knowledge Representation & Reasoning
• Spring 2004:
– CSE 510: Philosophy of Computer Science
– CSE 7xx: Seminar (probably on CVA)