Perception And Cognition - Concepts And Categories

Front 1

What are necessary and sufficient features?

Back 1

Necessary: if any of these features are missing, it is not a member of this category

Sufficient: if it has all the features, it is definitely a member of this category

Front 2

What is the first claim of the Classical View of Concept Formation?

Back 2

1. Concepts are mentally represented as definitions. A definition provides the necessary and sufficient features for membership to that category.

Front 3

What is the second claim of the Classical View of Concept Formation?

Back 3

2. Every object is either in or not in a category. There are no in between cases.

Front 4

What is the third claim of the Classical View of Concept Formation?

Back 4

3. Every member of category is thought to be as equally representative of a category as every other member.

Front 5

What is Family Resemblance?

Back 5

A weighted sum of the featural overlap amongst category members.

Front 6

What is the relationship between typicality and family resemblance?

Back 6

The graded typicality structure that we see inthe categories is well described by the featural overlap of the categorymembers

Front 7

What is the Polymorphous Concept Model?

Back 7

The representativeness of anexemplar is a function of the degree of overlap between the features associatedwith the exemplar and the features associated with the category.

Front 8

What is graded structure caused by?

Back 8

Thereappears to be shared variance between typicality and familiarity –butfamiliarity did not contribute to graded category structure

Front 9

What are some other variables that are related to graded structure?

Back 9

- Ageof Acquisition (the estimated age at which a word is learned)

- Wordfrequency (the frequency with which a word is found in text corpora)

- Imageability (the ease with which an object canbe pictured in your mind)

Front 10

What is the Contrast Model?

Back 10

According to the contrast model the similaritybetween the exemplars i and j can be calculated from the featurescommon to the two exemplars, the features of i that are not present in j,and the features of j that are notpresent in i

Front 11

What are other ways apart from MDS to represent similarity relations?

Back 11

- Additive trees

- Additive clustering

Front 12

What are some criticisms of similarity?

Back 12

- Our representations must be based on data far richer than similarity?

- By explaining everything, it explains nothing

Front 13

What is the prototype view?

Back 13

A category representation consists of asummary of all of the examples of the category

Front 14

What is the exemplar view?

Back 14

A conceptual representation consists of all the individual members of a category

Front 15

What are the costs of the prototype and exemplar view?

Back 15

- The prototype view is useful because it reducesmemory load; BUT–this reductioncomes at the cost of specific information

- The exemplar view is useful because it retainsspecific information; BUT it comesat a cost of memory load

Front 16

Is the Family Resemblance model exemplar or prototype?

Back 16

The familyresemblance model predicts typicality as a function of featural overlapbetween category members (exemplar)

Front 17

Is the Polymorphous Concept model exemplar or prototype?

Back 17

The familyresemblance model predicts typicality as a function of featural overlapbetween category members (exemplar)

Front 18

What is the prototype measure of typicality?

Back 18

Typicalitycan be predicted as a function of the distance between each category member ina multidimensional space and the central tendency of that category

Front 19

What is the exemplar measure of typicality?

Back 19

Typicalitycan also be predicted as a function of the mean distance between each categorymember in a multidimensional space and each other category member in that space

Front 20

What are the two phases of category learning experiments?

Back 20

- A learningphase – how long does it take/how well can you learn a category structure

- A transfer phase – presented with unseen stimuli from the categoryand make inferences about their category

Front 21

What is the process of category learning experiments?

Back 21

- In the Learning Phase participants are shownstimuli drawn from two categories

- They are asked if the stimulus is from categoryA or B

- They are given feedback

- They learn the categories over time

- Once the category structure is learntparticipants are shown a mixture of old and new stimuli, and asked tocategorize them.

- This gives us insight intoour ability to generalize from a stored category representation to novelstimuli

Front 22

What is the Generalised Context Model?

Back 22

The probability of a stimulus being categorizedas a member of a given category is a weighted function of the distance betweenthe target stimulus and the members of the two categories in the space(exemplar).

Front 23

What is the MDS-based Prototype Model?

Back 23

The probability of a stimulus being categorizedas a member of a given category is a weighted function of the distance betweenthe target stimulus and the prototypes (central tendencies) of the twocategories in the space

Front 24

What is the Varying Abstraction Model?

Back 24

Some form of partialabstraction could be used to describe the empirical categorizationdecisions

Front 25

What are the three levels of concept hierarchy?

Back 25

Super-ordinate, basic, and sub-ordinate

Front 26

What are the super-ordinate, basic, sub-ordinate levels?

Back 26

Front 27

What are the implications of the levels of the concept hierarchy?

Back 27

- Because of the high level of abstraction super-ordinate categories lack informativeness

- Sub-ordinate categories are highly informative, but lack distinctiveness

- Basic level categories appear to contain the best balance between informativeness and distinctiveness

Front 28

What are contrast categories?

Back 28

Categories that exist within the same domain, and at the same level of abstraction

Front 29

What is Tversky's Contrast Model?

Back 29

Accordingto the contrast model the similarity between the exemplars i and j can be calculatedfrom the features common to the two exemplars, the features of i that are not present in j, and the features of i that are not present in i

Front 30

What did Dry & Storm find regarding contrast categories?

Back 30

- Typical exemplars within one category wouldappear to have more features that are distinctive to their respective category, and fewerfeatures that are distinctive to the contrast category

- Common features tend to pull categoriestogether; distinctive features tend to help delineate the borders ofcategories.

Front 31

What is deductive reasoning?

Back 31

Involves using given true premises to reach aconclusion that is also true.

- Allmen are mortal.

- Socratesis a man.

- Therefore, Socrates is mortal.

Front 32

What is inductive reasoning?

Back 32

Isprobabilistic -it only states that, given the premises, the conclusion isprobable.

- 7-10%of males are red-green colour-blind.

- Joeis a male.

- Therefore, the probability that Joe is red-greencolour-blind is 7-10%

Front 33

What is premise monotonicity?

Back 33

- Whenmore categories are added to the premise the argument is stronger.

- Whennegative evidence is added, thelikelihood of accepting the conclusion should decrease

Front 34

What is premise diversity?

Back 34

Themore diverse the premise categories are, the stronger the argumen