Cognitive Psychology; Chapter 9 (pt 1)

Typicality Effect

ability to judge highly prototypical objects more rapidly

judgmenta of typicality:

can be independent from judgments -we rely on "other knowledge"to make category judgments. (EX. A lemon - painted with red and white stripes, injected with sugar to make it sweet, and then run over with a truck is still a lemon)

High Prototypicality (not important)

category member closely resembles the category prototype

Low Prototypicality ( not important)

category member does not closely resemble typical member of category

High Family Resemblance ( not important )

characteristics have a large amount of overlap with the characteristics of many other items in a category

Exemplar Reasoning

concepts and categories are organized around our knowledge (ex.A specific remember instance (i.e., an example of the category)

Conceptual Knowledge

is a mix of prototypes and exemplars -Early learning often involves exemplars -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

Prototype Approach to Categorization

membership in a category is determined by comparing the object to a prototype that represent the category (a central or "ideal" member of the category that possesses all the characteristic features)

semantic memory

memory for facts/events that is not tied to particular context -general knowledge ex: "capital of ohio is columbus"; "a touchdown is scored in football"

typicality influences judgment

people seem to find more typical (ex. fish one is more attractive because it is more typical)

Definitional Approach to Categorization

something is a member of a category based on it meeting the definition of the category. Does not work for natural/ human made objects. EX think chairs. There are different types of chairs

Prototype

the prototype theory suggests that category membership is judged based on their typicality—how much they resemble the prototype. ex : a white mug compared to 1)a brown mug and a 2) a weird shaped mug . the 1) brown mug is more typical in category of mugs

Prototypicality

variations within categories representing difference

What is a problem with definitional approach ?

It is always possible to find exceptions to our definitions, yet we still need to categorize the "exceptions" as members of the category/concept Example: "A dog is an animal with four legs that barks, has fur, and wags its tail" BUT an injured dog can also have 3-legs, a basenji breed dog yodels "does not" bark, and there are hairless chihuahuas

Family Resemblance

things in a particular category resemble one another in a number of ways because they are related to one another . *standard representation of a category are similar. ex in the image provided: the family members have similar hairline, ear, and beard

The Difficulties with Categorizing via Resemblance

-A toaster can be turned into a coffeepot -A skunk cannot be turned into a raccoon (even when it's made to resemble a racoon)

Basic-Level Categories

-Superordinate level (too general) (EX. FURNITURE) -Basic level (neither too general nor too specific) (EX.CHAIR) -Subordinate (too specific) (EX.WOODEN DESK CHAIR)

Basic concepts includes at least:

-a definition -a prototype -exemplars -we reason based on resemblance

**Basic level categories: Typical members

1)yield faster response times 2)usually named first 3)rated as more typical (the more the item looks like the prototype :its special . u can make judgment faster and name it fast)

how do we use prototype theory ?

1. specify the the prototype 2. compare items against the prototype to determine category membership

how do we use the Definitional Approach?

1.produce an exact meaning of a concept 2. Evaluate items based on the definition to determine membership ex: a dog is an animal with four legs and wags its tail.

Concept

Mental representation that is used for variety of cognitive functions (memory,term-41 reasoning) (ex: dterm-41og, shoe) allows us to apply general knowledge to new cases

Testing Prototype Type: Production task

Name as many fruits as you can. (many people will start with common fruits) -Participants generally name the most typical category members first then goes to more non typical (production means produce=give a list )

Prototypes

Provide an economical summary of the category

prototype theory and graded Membership

Objects close to a prototype (high typicality) are "better" members of the category than objects farther from the prototype (low typicality). ex: some dogs are "doggier" than other dog

The Difficulties with Categorizing via Resemblance

Opposite situation: objects that have all the typical features but are rejected as category members. • Example: a perfect counterfeit bill

Testing prototype theory: Sentence Verification Technique

Procedure to determine how rapidly people could answer questions about and objects category. Ex. yes or no. An apple is a fruit , a pomegranate is a fruit. *Faster responses when its higher prototypicality -a person would have a faster response to "is apple a fruit" compared to "is pomegranate as fruit"

Categorization

Process by which things are placed into groups called categories ** essential for understanding the world

exemplars

Provide information about category variability, but less economical

understanding concepts

Taken together, we rely on multiple streams of information to make judgments about concepts and category memberships

Family resemblance: how likely is an object belongs to a category ?

The more characteristic features of a category an object has, the more likely it is to belong to that category ex : it probably has four legs, probably barks, and probably wags its tail it is Probably A DOG - a creature without these features is unlikely to be a dog