Categories and Categorization Flashcards
Zoo Analogy
People visiting zoo from a faraway place - will be familiar with some concepts - permission to enter makes sense because they have the concept of exchange and private property
May not have concept of money
Have concept of animals so they will have some clear expectations about animals
Some concepts are universal - animals - while others are not
Everyone categorizes - what are developmental changes in categorization?
Everyone categorizes - we group objects and events into classes of like kinds
Groupings change in age-related, predictable ways
Younger children are more likely to refer to global perceptual features that can be seen - similarity of the broad shapes of objects
Older children - feature-by-feature comparison that older children prefer
Perceptual Category and Examples
An implicit classification of perceptual stimuli into discrete sets, despite a lack of physical discontinuity in the stimulus array (e.g. colors, facial expression, and consonant sounds).
EXAMPLE - Visible spectrum is physically, but not perceptually, continuous
Looks like there are dividing lines between the colours but there is no division
Even if the wavelength of the stimulus that meets our retina changes gradually from shorter to longer, our perception does not change gradually (categorical perception)
Morphed images - happy to sad - continuum - each photograph is equally physically distinct but there is a percept that there is something categorical here
Categorical Perception & Example
the perception of stimuli that differs continuously as being categorically or qualitatively different
That relatively fast change in perception associated with a gradual change in the physical characteristics of the stimulus is characteristics of categorical perception.
we more easily perceive differences in two color patches that cross our category boundary (e.g., what we would call a green and a blue) than we perceive differences of equal physical magnitude (the difference in wavelength is the same) within our perceptual category (e.g., two different blues).
Another example of perceptual categorization is the perception of speech sounds: As the physical stimulus changes gradually from “ba” to “pa,” we hear a sudden categorical change, even though we cannot hear the gradual change within either category
perception of emotional facial expressions is also categorical. For example, if a facial expression changes gradually from happy to surprised, the perception of a happy face changes rather quickly to the perception of a surprised face, relative to the physical change in the stimulus
Category
A mentally represented collection of entities
(objects, people, actions, or events).
psychological entity (the representation of the group) that is classified together for psychological reasons (some functional similarity)
without regard to any real-world grouping.
The Function of a Category - wrong reasons
Categories allow people to behave adaptively in a way that ultimately increases survival and reproductive success.
How do categories increase fitness?
PROPOSED REASON
Reason we categorize is because our cognitive and memory capacity would be swamped by information if we did not categorize
relieve memory load - NO
DOESN’T WORK BECAUSE
1. We remember the categories and individual items - remember all people in circle despite being in categories such as family and friends from school
2. There is no reason we couldn’t remember everything - remember category of family member but still have to remember each individual family member
—-Given number of synapses you have - you could remember everything in your lifetime
The Function of a Category - actual
Function is actually - inference - broader category - behave sensibly with respect to survival and reproduction - decisions that enhance fitness
Creating a category and then knowing that a particular object belongs in that category allows us to make inferences and thus provides a rich source of information regarding things that we are encountering for the first time.
Perceptually similarities but difference in category - informs behavior - house cat vs. wild cat - know what to expect from it, how it might benefit us and whether it is dangerous
How does the size of the category influence our predictions?
We can make broad predictions when we have large categories (if we know that the being we just encountered is an animal, we know it will move about to seek food)
more precise predictions with smaller categories (if we know that the being we just encountered is a bongo, we know it will grow horns, that it is a herbivore, and that its offspring will be bongos
to assign a new object that we encounter to a broad category such as “animal,” we need to know relatively little about it, but in order to assign a new object to a very specific category, more information is needed
Which types of categories are more effective for inference?
Even more effective with respect to inference are natural kinds categories (e.g. animals), as opposed to arbitrary categories (e.g. blue rectangles)
Categories are Functional
Krasnow Experiment
concepts are organized by our minds according to the value of objects where value means biological utility ex. Food
Value of should be a stronger categorization factor than how common or frequently occurring it is
-Visitors to alien planet and their job to compose a report on what they found
-taught participants two categories
of line-drawn coconut-shaped objects by presenting exemplar after exemplar and then testing how fast and accurate participants were at recognizing an example.
—-Wanted to know if people create categories by looking for
1. those items that are the most typical of the group
2. those that are the most useful or functional.
if told the category was a fruit, they were the fastest and most accurate at identifying a group member when the group member was ripe (as opposed to unripe).- evolutionary value
if not told not told that the category was fruit, then they showed the pattern consistent with the prototype view of
categorization: - most typical of the group.
Estimate of the value of items in evolutionary terms is part of what the mind uses to create categories
Krascum and Andrews - Wug and Gillie
Kids come into lab and are supposed to categorize these instances into two categories
One of the groups was given a functional description but given characteristics
Other was given a characteristic description but not a functional description
Group that hears the function is better at categorizing the drawings
Better at remembering a day later
Classic Category - Example
A category that can be defined by a list
of necessary and sufficient features.
is not just an idealized description of categories rather, categories are believed to
be mentally represented as definition
“raccoon,” there should be a list of necessary and sufficient features, and if all of the features are present, you have a raccoon. These features might include being four-legged, a mammal, native to North America, and furry with a dark facial mask, for example
Any entity that has all of the features should be included in the category
and any entity that lacks one or more of the features should not be included in the category.
Classic Category Features
All categories were classic
All categories were equally good categories
No distinction btw psychological and real-world categories
It is always possible to say whether an item is a member of a given category
1st PROBLEM with classic category - Wittgenstein
Game: What list of features includes all of these - Wittgenstein
Challenging classic view by asking what is the necessary and sufficient list that defines game
Basketball - competing, physical, teams, goal - how do we fit board games?
Has to exclude things that are not game - war, juggling, kicking ball
2nd & 3rd problems with Classic Category
Not supposed to be better examples - robin is a better example than a penguin -
Ambiguous Items
If you ask someone whether an olive is a fruit, or whether curtains are furniture, they may flip-flop and give you a different answer to the same question two weeks later
Are drapes furniture ?
Prototype View
viable response to Wittgenstein’s challenge to the classic view of categorization -Eleanor Rosch,
some members of a category are more central to that category than others because they more closely resemble the prototype.
More shared features - more central to the category
less prototypical member of the category if it shares features with members of other categories.
Problem with Similarity
Eleanor Rosch and her colleagues talk about categories, they were talking about psychological entities, not ideal or hypothetical groupings, as Plato was
Be aware here of your own instinct blindness because when Rosch talks about the similarity (or dissimilarity) between any two things, she is not talking about the properties of the actual objects; she is talking about our perceptions. Items are similar with respect to features that we see, that we notice, that are important to us and that we use to categorize objects
Associationists on Categorization
What evidence shows they’re wrong?
1- Committed to theory of classical categories
2 - Do not need to be functional
3 - Should not differ with respect to how richly inferential they are.
4 - Relies heavily on perceptual similarity.
DOESNT WORK -
1.induction studies
2. transformation studies
3. essentialism - the child’s intuition that some essence is responsible for conferring category membership to members of any natural category
Evolutionary Psychologists on Categorization
psychological processes underlying the formation of categories and concepts in children were selected for by natural selection.
categories regarding living things and other natural kinds are expected to be relatively UNIFORM compared to the infinite number of possible arbitrary categories that could exist.
The mental structures that support categories, concepts, and essentialism in developing children are characteristic of specialized design.
Core concepts have a long evolutionary history. Concepts that are reliably developing in infants and children are those concepts that were relevant in the EEA.
expect other species to have different categories, categories that are functional for them
Piaget’s View on Categorization - what method did he use?
He believed that any category was represented psychologically as a classic category and could be defined in terms of its necessary and sufficient features - whether arbitrary or natural
Free classification method to test children’s understandings of categorization.
Give them an array of different objects - free sort - create number of categories - decide how many categories - Thematic associations - dog, dog house, horse, stable
Piaget’s View on Categorization - what did he conclude?
Children in preoperational and concrete operational stages were perceptually bound -categorize based on visually perceivable features - if two red objects close - red is defining feature
—-Did not group into classic categories because they were cognitively immature - thematic - was an error and sign of immaturity
—–Children had complexes - A grouping that is more fluid and less well defined than a category and that does not rely on classic definitions.
Basic Levels and Hierarchical Organization
Categories are psychologically organized into hierarchies
Superordinate category - broader category - apples - species, specific orchard -
down to an individual apple - which isnt a category but an example- subordinate level categories
Thematic Association
The grouping of items based on their use
together or their prior association in a story
rather than on category membership.
Perceptually Bound
Compelled to categorize objects based
on visually perceivable features, as Piaget
thought children were