Module 9 - Concepts And Knowledge Flashcards
Which of the following statements is a problem for the classical view of categorization?
A. People can agree on a set of features that define “grandfathers”
B. People don’t find it unusual if asked to rate how birdy a bat is
C. People can give typicality ratings to well-defined categories
D. People are pretty good at categorizing even unusual category members.
B. People don’t find it unusual if asked to rate how “birdy” a bat is
What is schematic knowledge?
Our general background knowledge about something in the world that we gain through experience.
Ex: a child is more likely to be carrying a balloon then an adult.
On what kind of memory does knowledge depend on?
Semantic memory —> facts about the world
Which of the following is NOT a function of semantic knowledge?
A. Helps us predict how to behave in a new situation
B. Helps us make inferences about information
C. Helps us create an organized, connected understanding of the world
D. Helps us create meaningful connections to other people
D. Helps us create meaningful connections to other people
What is the difference between a category and a concept?
category
- set of items that are perceptually, biologically or functionally similar.
concept
- mental representation of objects, ideas or events.
- grouping things that are inside our minds.
What is the commonsense knowledge problem?
A problem in classic AI in which computers don’t possess the same commonsense knowledge as humans because knowledge has to be explicit in classic AI compared to humans’ ability to infer implicit knowledge
According to the classical view of categorization, how are categories defined?
They are defined by sets of defining features that are both necessary and sufficient for category membership. These features are necessary because without them category membership isn’t possible.
Consider Medin’s definition of concepts. When do you predict that infants would develop a concept of “cup”?
A. When their language has developed enough to produce the word
B. After they see an adult name and point to a cup
C. When their motor skills developed enough to use a cup
D. When their visual system has developed enough to see a cup clearly
C. When their motor skills have developed enough to use a cup
What are the issued with the classical view of categorization?
- Ex: dogs. How would you define them? 4 legs, hairy, barks. But what about dogs that have no fur, three legs or can’t bark. We still recognize them as dogs. It shows that it is nearly impossible to define features for most categories.
- The all or nothing rule. Things are either in the category perfectly or they are not. In reality, people can recognize that some things are not the best example of the category, but they are still in the category. Ex: how birdy are some animals (chicken, robin, ostrich, eagle, etc. )
What were the findings of Rosch’s experiments about categories?
He asked ps to rate items based on how good an example of a category the item was.
Ps could easily give typicality ratings, but they also agreed on the ratings
What are typicality effects?
Experimental effects where participants behave differently toward typical category members than atypical category members, suggesting that typical members have a privileged place in the category
Describe a lexical decision task.
Procedure where participants are shown a string of letters on a computer and are asked if they spell a word or not.
What is semantic priming?
Occurs when a person’s response time on a task is faster if it is preceded by a semantically related word compared to a word that isn’t semantically related.
Ex: first word apple, reaction time faster if second word is banada (same category of fruit) than if it is chair
What is the prototype theory of categorization?
Proposes that instead of relying on defining features to categorize items, we consider which features are most likely among category members.
characteristic features
- likely to belong to category but not REQUIRED.
Characteristic features are stored together in a __________________ of the category.
Prototype
What are the two difficulties found with prototype theory?
- Prototypes depend on context. Ex: here a robin is like a prototype for a bird, but in australia, it might be a rainbow lorikeet that is the prototype.
- How do we account for atypical category members? A penguin is a bird even though it is very far from the prototype.
What is the exemplar theory of categorization?
Proposes that we store actual examples of items we have encountered in the past.
Categorization occurs by comparing new items to the ones you have in memory and looking for similarity between their features.
Typicality effects are explained —> more easy to recognize typical examplars and it will take longer to recognize atypical examplars.
It also accounts for CONTEXT effects because it assumes that categorization depends on personal experience.
What are knowledge-based theories of categorization?
They propose that we rely on our broad knowledge base to explain the reasons for category membership. Our ideas about category membership are IMPLICIT.
