Week 13 Flashcards
Category
A set of entities that are equivalent in some way. Usually the items are similar to one another
Psychology of categories
Concerns how people learn, remember, and use informative categories. The core of intelligent behaviour
Concepts
Allow you to extend what you have learned about a limited number of objects to a potentially infinite set of entities
Two part definition that specifies what is in and out of the category
- Provides the necessary features for category membership: what must objects have in order to be in it
- Those features must be jointly sufficient for membership: If an object has those features, then it is in the category
Fuzzy category boundaries
Categories that have unclear boundaries that shift over time. Eg. A tomato can be considered a fruit or a vegetable
Typicality category boundaries
A related finding that turns out to be most important is that even among items that clearly are in a category, some seem to be “better” members than others. Eg. If someone says “there’s a bird in my yard”, the image will be a small bird rather than an ostrich or a penguin.
Prototype
The most typical category member
Less typical items
Items that are less and less similar to the prototype
Influences of typicality on cognition
Typical items are judged category members more often
speed of categorization is faster for typical items
typical members are learned before atypical ones, learning a category is easier if typical examples are provided
in language comprehension, references to typical members are understood more easily
In language production, people tend to say typical items before atypical ones
One possible answer to source of typicality
The frequency with which we encounter the object: we see a lot more robins than penguins, so they must be more typical. Frequency does have some effect, but it is not actually the most important variable
Family resemblance theory
Rosch and Mervis proposed that items are likely to be typical if they:
1. have the features that are frequent in the category
2. do not have features frequent in other categories
Categories within categories
Many important categories fall into hierarchies, in which more concrete categories are nested inside larger, abstract categories
The preference for which category we use to label things
The use of a single, consistent name helped children learn the name for things. Children’s first labels for categories tend to be exactly those names that adults prefer to use
Basic level of categorization
the neutral, preferred category for a given object, at an intermediate level of specificity.
Basic level categories are usually easier to learn. Children use these categories first in language learning, and superordinates are especially difficult for children to fully acquire
How is basic level of categorization not universal
Americans and many other people living in industrialized societies know so much less than our ancestors did about the natural world, so our basic level has “moved up” to what would have been the superordinate level a century ago.
