Rosch+(WK4)

=__“Principles of Categorization”, Rosch (notes wk 4)__ =

//Most, if not all, categories do not have clear-cut boundaries (p 10)//

 * Part 1 -** The two general principles that are proposed to underlie categorization systems (p. 27).

The first has to do with the function of category systems and asserts that the task of category systems is to provide maximum information with the least cognitive effort; the second has to do with the structure of the information so provided and asserts that the perceived world comes as structured information rather than as arbitrary or unpredictable attributes (p. 28).


 * Part 2 -** Shows the way in which these principles appear to result in a basic and primary level of categorization in the levels of abstraction in a taxonomy (p. 27).

In a programmatic series of experiments, we have attempted to argue that categories within taxonomies of concrete objects are structured such that there is generally one level of abstraction at which the most basic category cuts can be made (p. 30).


 * Part 3 -** Relates the principles of categorization to the formation of prototypes in those categories that are at the same level of abstraction in a taxonomy. In particular, this section attempts to clarify the operational concept of prototypicality and to separate that concept from claims concerning the role of prototypes in cognitive processing, representation, and learning for which there is little evidence (p. 28).


 * Part 4 -** Presents two issues that are problematical for the abstract principles of categorization stated in Part I: (1) the relation of context to basic level objects and prototypes; and (2) assumptions about the nature of the attributes of real-world objects that underlie the claim that there is structure in the world (p. 28).


 * Part 5 -** A report of initial attempts to base an analysis of the attributes, functions, and contexts of objects on a consideration of objects as props in culturally defined events (p. 28).

"It should be noted that the issues in categorization with which we are primarily concerned have to do with explaining the categories found in a culture and coded by the language of that culture at a particular point in time" (p. 28).

We categorize for the means of utility, both "behaviorally and cognitively" (p. 29).

Purpose of research: "to provide a systematic empirical sutdy of the co-occurrence of attributes in the most common taxonomies of bilological and man-made objects in out own culture" (p. 32).

__ Basic levels of abstraction: __ "Four investigations provided converging operational definitions of the basic level of abstraction," (p. 6) they are....

These objects are those that are perceived as similar because they occur in similar places or happen at similar times. Example: DEER, BEAR, and TREE are all things that may be categorized together because they are associated with forests.
 * 1) Common attributes: " ** co-occurrence of attributes in the most common taxonomies of biological and man-made objects in our culture" (pg 7)

**2) Motor Movements:** "Inseparable from the perceived attributes of objects are the ways in which humans habitually use or interact with those objects" (p. 33). Objects used on a regular basis are categorized together. (p. 8) Example: CAR, BUS, and BICYCLE, though they are not the same visually they are all used to transport people.

Objects that are alike in shape (p. 8)....BALL, ORANGE, and GLOBE.
 * 3) Similarity in shapes: ** "In order to be able to analyze cor-relational structures by different but converging methods, it is necessary to find a method of analyzing similarity in the visual aspects of the objects that was not dependent on subjects' descriptions" (pg 8)

**4) Identifiability of Averaged Shapes:** "if the basic level is the most inclusive level at which shapes of objects of a class are similar, a possible result of such similarity may be that the basic level is also the most inclusive level at which an averaged shape of an object can be recognized" (p. 34). *I found this stuff on page 9.....I think we have different page numbers.

^ "In summary, our four converging operational definitions of basic objects all indicated the same level of abstraction to be basic in our taxonomies" (p. 34).

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 * //Cognitive Economy//**: "as an organism, what one wishes to gain from one's categories is a great deal of information about the environment while conserving finite resources as much as possible". (p.28)=====

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Rather, the material objects of the world are perceived to possess **high correlational structure**." (p.29)
 * //Perceived World Structure//**: "unlike the sets of stimuli used in traditional laboratory-concept attainment tasks, the perceived world is **not** an unstructured total set of equiprobable cooccurring attruibutes.=====

__ **Traditional Areas of Study in Psychology** __

//Imagery: Since basic-level objects // contained the "most inclusive categories" then the basic-level must contain the most objects that come to mind as images. (p. 9)
=== //Perception: It is harder to categorize an object within broader or more detailed categories if it has not already been seen and recognized in their subordinate and superordinate categories. (p. 9-10) // === === //Development:// Children first begin to categorize objects in the basic-level. Example: every child first sees a ball as only a ball. Only later do they begin to categorize them into types of balls: GOLF BALL, BASKETBALL, BASEBALL, BOUNCEY BALL.......(p. 10) === === //Language:// The basic-level is possibly the origin of an object's name. When different types become available, then the subordinate category is born. When it becomes a part of a larger, broader category, then it becomes a part of the superordinate. (p. 10) ===

__**Definitions**__
-Cognitive Economy (p. 28-29): "the need to manage one's mental resources, including time, effort and specific processing tools" [|Glossary of Psychology]

-Perceived World Structure (p. 29): "The second principle of categorization asserts that unlike the sets of stimuli used in traditional laboratory-concept attainment tasks, the perceived world -is not an unstructured total set of equiprobable cooccurring attributes. Rather, the material objects of the world are perceived to possess high correlational structure."

-Categories (p. 30): " a number of objects that are considered equivalent. Categories are generally designated by names (e.g., dog, animal)."

-Taxonomy (p. 30): "A system by which categories are related to one another by means of class inclusion". Or, classification based on natural relationships (Webster's Dictionary).

-Level of abstraction (p. 30): "Is placed within a taxonomy and refers to a particular level of inclusiveness"