Frames

A structured knowledge representation, “the meaning of the meaning”

Think that a frame is a molecule rather than an atom

Cognative processing w/ frames is bottom up (from natural languang to representation) and top down (from memory to structured representation).

Stereotypes are cognatively efficient, so frames represent stereotypes

Structure of Frames

A frame is a knowledge structure

Ashok ate a frog:

Ate (verb frame)
    Subject: Ashok
    Object: Frog
    Location: Stomach (now)
    Time: past
    Utensils: ?
    Object-Alive: False
    Object-is: in-subject
    Subject-mood: Happy

Slots (Subject, Object, etc.) & Fillers (Ashok, Frog, etc.)

Slots on a frame can have a pointer to another frame, for instance the Subject slot above could point to a noun-frame of Ashok. Allows for a discourse level understanding rather than a sentence level understanding.

Ate (verb)
    Subject: -> Ashok

Ashok (noun)
    Title: Professor
    Location: Atlanta, GA

Properties of Frames

• Frames represent stereotypes of the key word for the frame, like Ate
• Provides default values
• Takes advantage of inheritance and instances

Animal
    num-arms: (default value)
    num-legs: (default value)

Human (type of animal) - Class
    num-arms: 2
    num-legs: 2
    job:
    name:

Human (type of animal) - Instance
    num-arms: 2
    num-legs: 2
    job: Professor
    name: Ashok

• Frames can be used to as a structured representation to store a sentence of input, and can be used to generate a sentence of output.

Representations

Similar to semantic nets, production systems

1) Ate gets added to the working memory 2) The slots and default filler values get loaded from semantic memory into working mem

Story Understanding