Knowledge Flashcards
Category
A group of objects that belong to the same class of objects
What categories are useful for
Sorting
Understanding the world
Understanding new cases
Tools for making inferences ("What does this look like?")
Understanding strange behaviorsThree approaches to categorization
Definitional approach
Prototype approach
Exemplar approach
Definitional approach
Each category has a definition
If an item fits the definition, it belongs in that category
Limitation of definitional approach
Some things can’t be categorized
Not all things in a particular category exactly match the definition
Family resemblance
Things in the same category resemble one another, even if they don’t fit the definition
Solves problem to definitional approach: allows for some variation within a category
Prototype approach
Membership in a category is determined by comparing the object to a prototype that represents the category
Prototype isn’t an actual member of the category, but an “average” representation of the category
High vs. low prototypicality
High: category member closely resembles the category prototype (it is like a “typical” member of the category
Low: category member doesn’t closely resemble a typical member of the category
Typicality effect
Rating on 7 point scale: how representative different examples of category are
(low number: representative- apple or robin; high number: not representative-pumpkin or bat)
We tend to have a pretty good agreement on what is prototypical
The closer the exemplar is to the prototypical, the faster we will be able to identify it
Priming
Presentation of 1 stimulus facilitates the response to another stimulus that usually follows closely in time
Results of priming experiment (prototypical approach)
People identify matches of colors that fit given prototype (“blue”) more quickly than matches of colors that don’t fit given prototype (yellow when priming word was “green”)
Exemplar approach
Determining whether object is similar to actual examples of that object (exemplars)
Examples closer to exemplar are classified faster
Advantage over prototype approach: handles atypical cases
Hierarchical organization
Larger, more general categories are divided into smaller, more specific categories
Example: carnivores -> felines -> cat, puma, lynx
3 category levels
Superordinate -> basic -> subordinate
Basic category level
Specific examples (ex- bed, chair, table) Below superordinate, but above subordinate
