7 - Concepts And Categories Flashcards
Concepts allow us to
- apply general knowledge to new cases
- draw broad conclusions from experiences
Ex: know what a dog looks like, can identify others
What does it mean for a concept to be definitional
- have definition in mind
- for dog, could be animal with 4 legs that barks and wags tail
- if something fits that definition, they’re classified as a dog
What problem do we have with defining concepts?
- it’s always possible to find exceptions to our definitions
Eg. Tables are flat surfaces with 4 legs
How can we solve the problem of the definitional approach to defining concepts?
- focus on family resemblance of members within a category
- no ‘defining features’, have various features
Take definition of category and add probabilistic statements (ex. usually have dark hair or glasses) - allows for exceptions, for the most part can capture main features of items
Define family resemblance
The more characteristic features an item has, the more likely you are to belong to that category but they don’t need to have all the characteristics
Describe prototype theory
- the category is characterized by a central member that possesses all the characteristic features (the prototype)
- take all features, create one prototype that becomes mental representation of what members of group look like
- your IDEAL EXAMPLE, combination of all
- category membership is judged based on typicality
Define typicality
How typical is the item that your experiencing
- how much does it resemble the prototype
Define graded membership
Objects close to a prototype are better members of the category than objects farther from the prototype
What are the 3 methods for testing the prototype theory?
Sentence verification task, production task, rating tasks
describe the sentence verification task
- given sentence, have to state if the statement is true or false
- the dependent measure is how fast they answer/make judgement
- usually make correct judgment but timing is different
what is the theory behind the sentence verification task?
judgements about items that are more distance from the prototype take more time to make
*ex. robins are bird = small distance in prototype theory network vs penguins
what is the theory behind the production task?
participants generally name the most typical category members first
*these typical category members are also those that yield the faster response times in the sentence verification task
describe the production task
- participants have to name as many items in a category as they can (ex. fruits/birds)
*you have network of all the birds you know, in center is prototype
*animals you come up with are compared with prototype, start with most typical
what’s the theory behind rating tasks?
items that are closer to the prototype are rated as more typical of the category
describe rating tasks
- given a bunch of exemplars/items from a category and asked to rate them according to which is closest to the prototype
*ranking from 1-7
what’s another name for items at the top of a rating task list?
priveleged items
*so close to prototype that if you think of the concept, you think of items at the top of the list
*top is apple, olives lowly ranked
basic level categories are…
- represented by a single word
- default for naming objects
- easy to explain commonalities
- basic categories learned first (ex. apple is one of first truits you learn)
what is the spectrum of basic level categories (what is this object)
too general > too specific
ex. furniture>bench>metal bench outside HSC
*the middle is the basic level category, has the biggest consensus among majority of ppl
define exemplar-based reasoning
in some cases, categorization relies on knowledge about specific category members (exemplars) rather than the prototype
summarize general differences between prototypes and exemplars
- prototypes provide an economical summary of the category
- exemplars provide info about category variability, but less economical
- are easier to adjust categories based on exemplars than prototypes
- instances of items in category
describe exemplar characteristics in more depth
- have lots of exemplars in mind that represent the concept
- the ones you interact with most will be at top of list
- ex. don’t have single prototypical fruit to represent category of fruits but in your concept of fruits all of the examples of fruit are in there
is the prototype theory or exemplar theory better?
neither, sometimes rely on exemplar-based reasoning, and sometimes more prototype based reasoning
*in cases when we need to think of a specific example, the prototype theory has a hard time explaining it
describe prototype theory characteristics in more detail
- provide us with economical summary of category, quicker understanding of what items in category look like
why is it important for exemplar theory to consider category variability?
- more likely to welcome new items into category than if you had more narrow/low variabiliy set of examples of what belongs in category
which theory makes it easier to adjust categories
exemplars
*new item will have very minimal effect on what prototype looks like
which theory is involved in early learning?
early learning involves exemplars
*as you become more fluent with category, you develop prototypes for it
*experts go back to having individual exemplars (ex. birders)
how does experience affect the use of exemplars and prototypes?
- experience often involves averaging exemplars to get prototypes
- with more experience, we can use both exemplars and prototypes to ascertain category membership and recognize objects
