Week 8 Knowledge Flashcards
what kind of system of knowledge do humans use
distributed
what is a concept
mental representation of an object, event or pattern
decreases the amount of info to learn
allows us to make predictions
category
class of things that share a similarity
concepts are organized into this
Definitional Approach (forming concepts/categories)
to belong to a category you need necessary/sufficient features
absolute (can make it hard to find specific features)
rigid boundaries
all members are equally good examples
learning involves discovering defining features
the two types of probabilistic theories
prototype
exemplar
both based on experience
prototype theory
categories made on an idealized average
the prototype
prototypes have high family resemblance
exemplar theory
idealistic representation
category decisions based on all of the examples stored in memory
more flexible as you generate a prototype for the situation you are in
takes into account atypical cases and explains the typicality effect
easily deals with variable categories/allows overlap
if something is more similar to the prototype are you faster or slower to categorize it
faster
typicality effects
we are slower to categorize something that is not as similar (typical) to the prototype of the category
difference of how close something is to the prototype is called the __
typicality
problems with prototypes
edge cases: overlap of features might mean something should be in a diff category
we lose individuality of each concept/object
characteristics of categories
graded membership (some exemplars are better exemplars than others)
family resemblance (members of a category typically share common features)
related concepts (central tendencies, typicality effects)
the three main levels of categorization
superordinate (groups basic levels)
basic (level where members share most of the attributes of the category)
subordinate (more specific than basic)
explain how knowledge affects categorization
the more we know about a topic the more likely the subordinate becomes your basic level for categorization
Semantic Hierarchal Theory
semantic: general facts and info
information that is related is linked together, when one node is activated it makes it easier/faster to think of the connecting nodes
nodes and links
activation spreads
what model explains priming
semantic hierarchal theory
priming facilitates the activation of related concepts
categories and nodes have ___
properties (sing, fly, skin)
generalizations of semantic hierarchy
DRM paradigm: theme word not present although you recall it
lexical decision task (process cow faster with milk than with wall)
issues with semantic hierarchy
cannot explain typicality effects (canary is a bird and ostrich is a bird are same distance away, but have different reaction times)
cognitive economy (closeness of nodes = faster) is not always true
-faster to say a horse is an animal rather than a mammal
family resemblance theory was a jumping point from what theory to the next
definitional to prototype
naming effect
people more likely to list things of high-protoypicality before low-prototypicality items
how does exemplar theory explain typicality effect
as exemplars are based on what we have experienced in the past, reaction times are faster for better category items that we see more of, but our knowledge still holds space for those of lower typicality
learning a cateogory often involves a shift from ___ to ____
prototype to exemplar thinking
explain the gain and loss of information between organizational leevels
common features
- global 3
-basic: 9
-specific; 10.3
big loss of info going global but only slight gain going more specific
