CLPS 0020- Lectures - Categorization Flashcards
Why is it easier to process/categorize nonliving vs living objects?
Nonliving may include a motor component as well as visual, like scissors vs birds
What are the two theories of categorization?
category-based and property based
What is the category based theory of categorization?
animals vs fruits vs rocks vs tools, etc.
What is the property-based theory of categorization?
color, texture, shape, use, place found, etc: combination of these features that ultimately builds a category
What happens in the brain with words related to pick/kick/lick?
words related to the movements activate similar brain areas: kicking activates similar regions to foot/punt, etc.
What did Myung et al show about looking for piano pictures?
When looking for piano picture, gaze will go more frequently to “typewriter” when searching than unrelated pictures like “apple”
Is categorization restricted simple features?
No, need access to different types of info when categorizing
Why are categories important?
can’t make sense of experiences if every object is unique, can’t learn how to interact or make predictions about properties, can’t communicate about objects if every instance is unique, not economical
What comprises a category/class of objects?
exemplars
What is the classical view of categorization?”
symbol classification: defined like dictionary entires: if we see a dog, we check the list of defining features and match it or not; problem: counterexamples such as stuffed toy dog
What is another view of categorization besides the classical view?
taxonomy: define birds as animals, so if you define a bird exemplar, it’s given that it’s an animal
What empirical finding supports the taxonomy model of categorization?
Reaction time: shorter RT for smaller distances moved on the hierarchy
What is a counterexample to the taxonomy model’s RT finding?
Canary fish vs canary gills: should take a long time to go up the hierarchy to fish adn then down to gills, but it doesn’t: we know very quickly that canaries don’t have gills
What are five other characteristics/components of categorization?
Probabilistic, family of resemblances, graded membership, typicality effect, fuzzy boundaries
What does it mean that categories are probabilistic?
if it has this property, then there’s this chance that it’s in such a category
What does it mean that categorization features a family of resemblances?
concepts organized around properties that may be characteristic of category members
What does it mean that categorization features graded membership?
it’s not all or none: an object could be a category or something and less in the category of another or more in the category of something else
What does it mean that categorization features the typicality effect?
some members are more typical than others: better exemplars
What does it mean that categorization features fuzzy boundaries?
due to the probabilistic nature of categories, it may be hard to tell if an object is in one category or the other
What does “list all birds” show about categorization?
Typicality effect: certain exemplars are better exemplars thatn other, like robin to penguin
What does “how much of a fruit is an apple” show about categorization?
Typicality effect: apples are better exemplars than tomatoes of fruit
What does “apple is a fruit yes or no” response time say about categorization?
Typicality effect: certain exemplars take less time to identify as members of that category
What is important when looking at the typicality effect? What determines if something is more typical, generally?
Experience
What does “cup or bowl” show about categorization?
graded categories/fuzzy boundaries: not everyone agrees where things fall on the spectrum: can be attributed to experience
What can alter categorization of an object besides experience?
context: consider cup/bowl with coffee/oatmeal
What are the two theories of the nature of the representations in categorization?
prototype theory and exemplar theory
What is the prototype theory?
That the brain stores the average of the exemplars: only the most common features
What is the exemplar theory?
That the brain stores the best/most typical exemplar, not an average
How does categorization work according to the prototype theory?
You compare the stimulus to the prototype average and see how well it matches up
What are the problems with the prototype theory?
when you average, you lose information; doesn’t tell you how variable a set might be; and how do we know so much about fine details then?
How does categorization work according to the exemplar theory?
You compare the stimulus to examples of a category and see how well it matches up
What are the problems with the exemplar theory?
Not economical: how do you remember all the details
What are the beenfits to the exemplar theory of categorization?
learn/store individual members, accounts for typicality and frequency, retains variability and details, influence by context
What is one test to determine whether categorization follows the prototype or exemplar theory?
Test reaction time in identifying new stimuli: show examples of both a similar image to the others (exemplar) or an average of the others (prototype); but depends on set size: if fewer objects, remember more details and follow exemplar theory; if more objects, don’t remember details and follow prototype theory
In the prototype vs exemplar experiment, what set size is associated with the exemplar theory?
Smaller
In the prototype vs exemplar experiment, what set size is associated with the prototype theory?
Larger
What is probably the accurate model of categorization?
A combination of both the prototype and exemplar theories
Which visual field is biased towards trained exemplars?
LH/RVF: prefers language, interested in difference
Whcih visual field is biased toward prototypes?
RH/LVF: doesn’t really care about details because it doesn’t have to deal with language-type things
