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Conceptual Dependency (CD)

Conceptual Dependency originally developed to represent knowledge acquired from natural language input.

The goals of this theory are:

It has been used by many programs that portend to understand English (MARGIE, SAM, PAM). CD developed by Schank et al. as were the previous examples.

CD provides:

Sentences are represented as a series of diagrams depicting actions using both abstract and real physical situations.

Examples of Primitive Acts are:

ATRANS
-- Transfer of an abstract relationship. e.g. give.
PTRANS
-- Transfer of the physical location of an object. e.g. go.
PROPEL
-- Application of a physical force to an object. e.g. push.
MTRANS
-- Transfer of mental information. e.g. tell.
MBUILD
-- Construct new information from old. e.g. decide.
SPEAK
-- Utter a sound. e.g. say.

ATTEND
-- Focus a sense on a stimulus. e.g. listen, watch.
MOVE
-- Movement of a body part by owner. e.g. punch, kick.
GRASP
-- Actor grasping an object. e.g. clutch.
INGEST
-- Actor ingesting an object. e.g. eat.
EXPEL
-- Actor getting rid of an object from body. e.g. ????.

Six primitive conceptual categories provide building blocks which are the set of allowable dependencies in the concepts in a sentence:

PP
-- Real world objects.
ACT
-- Real world actions.
PA
-- Attributes of objects.
AA
-- Attributes of actions.
T
-- Times.
LOC
-- Locations.

How do we connect these things together?

Consider the example:

John gives Mary a book




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So the past tense of the above example:

John gave Mary a book becomes:




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The tex2html_wrap_inline7304 has an object (actor), PP and action, ACT. I.e. PP tex2html_wrap_inline7304 ACT. The triplearrow (tex2html_wrap_inline7316) is also a two link but between an object, PP, and its attribute, PA. I.e. PP tex2html_wrap_inline7316 PA.

It represents isa type dependencies. E.g

Dave tex2html_wrap_inline7316 lecturerDave is a lecturer.

Primitive states are used to describe many state descriptions such as height, health, mental state, physical state.

There are many more physical states than primitive actions. They use a numeric scale.

E.g. John tex2html_wrap_inline7316 height(+10) John is the tallest John tex2html_wrap_inline7316 height(< average) John is short Frank Zappa tex2html_wrap_inline7316 health(-10) Frank Zappa is dead Dave tex2html_wrap_inline7316 mental_state(-10) Dave is sad Vase tex2html_wrap_inline7316 physical_state(-10) The vase is broken

You can also specify things like the time of occurrence in the relation ship.

For Example: John gave Mary the book yesterday


picture1049

Now let us consider a more complex sentence: Since smoking can kill you, I stopped Lets look at how we represent the inference that smoking can kill:




picture1082

To add the fact that I stopped smoking




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Advantages of CD:

Disadvantages of CD:

Applications of CD:

MARGIE
(Meaning Analysis, Response Generation and Inference on English) -- model natural language understanding.
SAM
(Script Applier Mechanism) -- Scripts to understand stories. See next section.
PAM
(Plan Applier Mechanism) -- Scripts to understand stories.

Schank et al. developed all of the above.


next up previous
Next: Scripts Up: Strong Slot and Filler Previous: Strong Slot and Filler

dave@cs.cf.ac.uk