1.
basic-level categorization: A level of categorization hypothesized as the "natural" and most informative level, neither too specific nor too general.
2.
exemplar-based reasoning: Reasoning that draws on knowledge about specific category members, rather than drawing on more-general information about the overall category.
3.
family resemblance: The notion that members of a category (e.g., all dogs, all games) resemble each other. In general, relies on some number of features being shared by any group of category members, even though these features may not be shared by all members of the category.
4.
fuzzy boundary: A distinction between categories that identifies each instance only as more or less likely to be in a category, rather than specifying whether each instance is or is not included in the category.
5.
graded membership: The idea that some members of a category are "better" members and therefore are more firmly in the category than other members.
6.
Heuristic: A strategy that is reasonably efficient and works most of the time. In using one, it is in effect choosing to accept some risk of error in order to gain efficiency.
7.
picture-identification task: A task in which a person is shown simple pictures (often line drawings) and must indicate, as rapidly as possible, what the picture shows (e.g., "a dog," "a truck"). Responses tend to be faster if the objects shown are typical of their category.
8.
production task: An experimental procedure used in studying concepts, in which the person is asked to name as many examples (e.g., as many fruits) as possible.
9.
prototype theory: The claim that mental categories are represented by means of a single "best example," or prototype, identifying the "center" of the category. In this view, decisions about category membership, and inferences about the category, are made with reference to this best example, often an average of the examples of that category that one has actually encountered.
10.
rating task: A task in which research participants must evaluate some item or category with reference to some dimension, usually expressing their response in terms of some number.
11.
sentence verification task: An experimental procedure, used for studying memory, in which participants are given simple sentences (e.g., "Cats are animals") and must respond as quickly as possible whether the sentence is true or false.
