Books
in black and white
Main menu
Home About us Share a book
Books
Biology Business Chemistry Computers Culture Economics Fiction Games Guide History Management Mathematical Medicine Mental Fitnes Physics Psychology Scince Sport Technics
Ads

Dynamic Memory. A Theory of Reminding and Learning in Computers and People - Schank R.C.

Schank R.C. Dynamic Memory. A Theory of Reminding and Learning in Computers and People - Cambridge University Press, 1982. - 250 p.
Download (direct link): dinamycmemory1982.djvu
Previous << 1 .. 95 96 97 98 99 100 < 101 > 102 103 104 105 .. 106 >> Next

Letís consider the scene ORDER again. We have suggested that ORDER is a scene that contains information regarding any societal interaction between two people where one of those people represents a business of some type and the other is a client requesting a service that that business provides. We argued that we have information about such scenes apart from any particular physical instantiation that that scene might take.
In our treatment of ORDER in this book, we have connected ORDER to five different entities that are in some sense higher than it. We have said that ORDER is part of many MOPs that request services. Thus ORDER is part of M-RESTAURANT, M-STORE, M-PROVIDE-SERVICE and so on. Further, we have said that ORDER is related to D-AGENCY. That relationship is hierarchical in nature. ORDER is an instance of the more general goal of getting someone to do something for you.
What we want to claim is that these two relationships are ubiquitous among all the structures we have been proposing. That is, every structure is related to a higher level structure that includes the first structure as part of the particular relationships. Further, every structure is related to a higher level structure that abstracts out the aspects of that structure that apply at a higher level of generalization. Specifically, every scene is packaged by one structure and relates to another structure by abstraction.
It follows, if the above is true, then since the structures that are holding the information about packaging and abstraction are themselves structures, that any structure that packages one structure, abstracts another. Also any structure that abstracts one structure, must package another.
220
Dynamic memory
mM-TRIP
U-MOP
D-AGENCY
M-RESTAURANT PRECONDITION TO
ORDER
abs
$REST-ORDER
$STORE-ORDER
Figure 12
This being the case, we might ask what structures package and abstract M-RESTAURANT, and what structure M-RESTAURANT packages and abstracts,. Similarly we might ask what structures ORDER packages and abstracts. In the case of M-RESTAURANT it should be clear that the meta-MOPs that use M-RESTAURANT are its packaging structures. For example mM-TRIP or mM-DAY-AT-OFFICE can use M-RESTAURANT to fill one of its slots.
The structure that abstracts M-RESTAURANT is the Universal MOP. The Universal MOP has information in it about the abstract relationships that hold in M-RESTAURANT. Since the Universal MOP is also a structure, it must not only abstract, it must also package, Clearly it packages universal scenes.
ORDER clearly abstracts scripts. Its role in memory is to take out the information in a script and move it to the next level of abstraction. But does ORDER package anything?
To see the loose ends here, letís consider the relationship among what we have discussed so far (Figure 12).
What we have here are the relationships for ORDER that we specified. Two differences from what we said are apparent. One is that ORDER does not package anything. The second is that since the Universal MOP packages universal scenes, given its place in the above structure, what it
Some perspective
221
meta-MOP
package
U-MOP D-goal
package /abstract
UNIVERSAL SCENE
package
abstract
GENERALIZED SCENE
'abstract SCRIPT
Figure 13
packages must also be what abstracts ORDER This cannot be D-AGENCY. It is, in fact, the PRECONDITION TO SERVICE universal scene that abstracts that generalized scene ORDER.
Now, taking the specifics out of the diagram, we have Figure 13.
The key point here is that whatever structure we propose as a packaging mechanism for a given structure, must have an abstract that seems to package the structure that abstracts the original structure. Or, to put this another way, the relationship identified by Figure 14 means that structures A and D share a great deal. Whatever D packages must abstract A and whatever D abstracts must package A.
A theory of successive abstractions
This basic structure is the epitome of a theory of successive abstractions, which is the essence of what we have been proposing here. The theory is a simple one. For every event that we process, we attempt to relate it to what we know, that is, what we have previously processed and stored in memory.
Each event thus gets processed in terms of like events. But like can get defined in a great many different ways. An event can be similar to another in any number of ways. Similarity depends upon the degree to which we are willing to abstract.
222
Dynamic memory
D-
/
abstract
package
\
¬

\
/
package
abstract
Figure 14
How is a pencil like a log? How is a butterfly like a mountain? They are either identical or else can be seen as similar in some way. Seeing similarities is the essence of generalization.
Our theory then, is that there are a variety of structures in memory, each abstracting out certain features of an event in such a way as to make that structure general enough to be of use in representing information from distinctly different events that are similar to the extent that they can share elements of the same structure.
Previous << 1 .. 95 96 97 98 99 100 < 101 > 102 103 104 105 .. 106 >> Next