Final _ chapter 9 Flashcards
(56 cards)
Conceptual Knowledge
- Knowledge that enables us to recognize objects and events
- and to make inferences about their properties
This knowledge exists in the form of concepts
Concepts
- Allows people to discriminate members of a categorie from non-members.
- A Mental representation of a class or individual.
What is the difference between a concept and a category?
A person’s idea about what should and shouldn’t go in a category is their concept of that category.
- A concept refers to a mentally possessed idea or notion
- A category refers to a set of entities that are grouped together.
Categories
- Facilitate the storage and retrieval of information.
- supplies a principle of organization by which new information can be banked efficiently in memory.
- Provides rules and road maps to accessing information.
We categories to organize concepts
Categorization in use
- You recognize a perceived input
- find its category in your internal mind map
- You are then able to focus your energy on specifying what’s special about that particular input.
Relates each experienced entity to an extant representation
Definitional Approach
How are objects placed into categories?
- Classical view
- Deciding whether something is a member of a category by determining whether a particular object meets the definition of the category
[Cons]
- Works well for well defined concepts [geometric shapes],
- Not so will for complex ones.
[E.g.]
- Different objects with drastically different features can be considered chairs.
Ludwig Wittgentein [1953]
Noted the problem of the definitional approach
and proposed the idea of family resemblance
- Referes to the idea that things in a particular category resemble one another in a number of ways.
Allows for some variation within a category
Prototype Approach
How are objects placed into categories?
Membership in a category is determined by compairing the object to a prototype that represents the category
A ‘typical’ member of the category
Eleanor Rosh [1973]
Proposed that the ‘typical’ prototype is based on an average of members of a category that are **commonly **experienced.
- Thus the prototype is not an actual member of the category, but an average representation of the category.
Typicality
[High typicality]
- Means that a category member closely resembles the category prototype.
- A ‘typical’ member of the category
[Low typicality]
- Means that the category member does not closely resemble a typical member of the category.
Rosh et Al. [1975]
Experiment
Investigated the basic nature of categories and quantified the idea of typicality.
- Presented participants with a category title [e.g. bird] and a list of about 50 members of the category.
- Participants were tasked to rate the typicality on a 7-point scale [1-high and 7-low/ is not a member at all]
[Results]
- [1.18 rating for sparrow] reflects the fact that most people consider a sparrow a good example
- [4.53 rating for penguin]
- [6.15 rating for bats] reflect they are not considered good examples.
Typicality and family resemblance
Prototype effects
High typicality category members have a higher family resemblance
[In a study done by Rosch and Mervis]
- Good examples of a category share many attributes with other members of this category
- While those that were rated as bad examples didn’t.
- They concluded that there is a strong relationship between family resemblance and prototypicality.
Sentence Verification Technique
Method
-Participants are presented with statements and are asked to answer
- yes is they think the statement is true
- No if they think it isn’t
Typicality Effect
Prototype effects
Ability to judge highly prototypical objects more rapidly
[In a study done by Smith et al 1974]
- Used the sentence verification technique to determine how fast people could answer questions about an object’s category.
- Highly typical category members were responded to faster
- E.g ‘Is an orange a fruit?’ faster than ‘Is a papaya a fruit?’
Highly typical category members are primed more effectively
Naming
Prototype effects
When participants are asked to list as many objects in a category as possible
- They tend to list the most prototypical members first
[E.g] sparow would be named before penguin
Priming
Prototype effects
Occurs when presentation of one stimuli facilitates the response to another stimuli that usually follows closely in time.
[In Rosch’s experiment]
- Participants first hear the prime [name of a color]
- 2 secs later they saw a pair of colors side by side
- They we asked to indicate whether the two colors were the same or different
[results]
- When participants hear the word green, they judged two patches of primary green as being the same more rapidly than two patched of light green
- The prime facilitated response to a stimuli if it contained some of the information needed to respond to the stimuli.
Name the 4 effects of prototypicality.
- Family resembance
- Typicality
- Naming
- Priming
Examplar Approach
How are objects placed into categories?
- Suggest a category is defined based on a set of strored examplars
- Membership in a category is determined by comparing a target to stored members of the category
Takes into account the wide variation among items in a category
Examplars
Actual members of the category that a person has encounted in the past.
How does the examplar approach compair to the prototype approach?
Like the prototype approach, involves determining whether an object is similar to others
But, instead of an average..
- The standard for the examplar approach involves many examples
- each called an examplar
The examplar approach explains the typicality effect
- By proposing that objects that are like more of the examplars are classified faster
Similar to the idea of family resemblance as well
Advantages of the examplar approach
- By using real examples, it can more easily take into account atypical cases [flightless birds]
- The ability to take into account individual cases, means that no information that might be useful later is discarded
- Requires only that we remember varying examples
Exemplars and prototypes working together
It has been proposed that as we initially learn about a category, we may average exemplars into a prototype, but as we learn, individual exemplars become stronger.
- Early in learning we would be poor at taking exceptions into account
- later on exemplars for these cases would be added to the category
- Both produce our rich store of conceptual knowledge allowing each kind of knowledge to explain the tasks that are most suited for it.
[E.g]
- we know generally what cats are [prototype]
- But we know our own specific cat the best [exemplar]
Hierachical Organization
kind of organization in which larger more general categories are divided into smaller more specific categories creating a number of levels of categories.
Colour Categories
After a color spectrum classification task
[Regier et al. 2007]
- Concluded that there are universal properties that guide the development of colour categories in different languages
- However there is a variation from language to language
- Suggested that warmer colours are more useful and more likely to be named
