Cognitive Psychology: Concepts and Categories

family resemblance

all attributes that a member has in common with all the other members of a category; typical members have high score

prototype

an average family member; best example of a concept

typicality gradient

an ordering of the members of the category by their relative typicality scores; good predictor of the time subjects take to make verification judgements; states that some members of a category are regarded as more typical than others; a category can be described in terms the _________ of its members

causal inference

used between external observable features and internal states; what is the relationship between observable and internal features?

conjunction strategy

used when the category-based induction is based on the exemplars with the conjunction of the given and target feature

Malt and Smith

(people) 1983; opposed prototype theory on the grounds that the theory is incomplete; it does not account for the fact that people seem to know about relations between attributes rather than just attributes alone; some attributes are better indications than others

Rips and Collins

(people) 1993; exemplar view preserves the variability of instances in the category, whereas a prototype is a type of average that excludes variability

Seger et al

(people) 2000; fMRI study, classifying abstract paintings. RH processes specific stimuli, LH processes abstract stimuli/ novelty vs automaticity?

Laeng et al

(people) 2003; hemispheric processing differences between the subordinate (RH) and basic-level (LH) categories/ concrete vs linguistic?

Chin-Parker and Ross

(people) 2004); within-category (inference) or between-category (diagnostic) features used, depending on task; prototype vs exemplar; in both inference and clarification tasks, diagnostic features are used; make drawings and train people to recognize as Deeger, Lokad, Koozle, and Himlit; come up with categories that are defined by certain attributes (e.g. Koozle antenna) that are diagnostic for certain categories; inference task: if you are a Koozle, you will have a certain type of antenna; how do we represent the information in each category?

Rehder and Kim

(people) 2009; observable features are more diagnostic to category membership if they are caused by an underlying feature that defines category membership

Murphy and Ross

(people) 2010; category-based induction; pointed out that categorization by itself is not very useful; people do not clarify things for the sake of clarifying them - they do it to make a prediction about those things; e.g. having decided that a certain object is a dog, you can predict that it might bite = inductive inference from categories; people used feature-feature correlation within a category - does a feature predict another - rather than category summary information; given a property of an object (e.g. yellow) and asked what child likely drew it (e.g. Maura because 5/6 total yellow shapes were drawn by Maura) suggests that feature-feature correlation is important for determining what constitutes everyday ad-hoc categories; when making predictions, people do not assume that features are independent - use conjunction strategy

Rosch et al

(people); showed that basic-level categories have special properties not shared by categories at other levels: 1. first words are learned at the basic level, 2. we name objects at the basic level faster, 3. participants list attributes of the basic level easily

Frege

(person) 1952; distinguished between a concept's intension and extension

Hapton

(person) 1981; opposed prototype theory on the grounds that not all concepts have prototypic characteristics; e.g. what about abstract nouns like 'truth'?

Keil

(person) 1989; children understood internal attributes; e.g. a raccoon dyed black and given an odoured sac was still a raccoon, not a skunk (despite looking like one); attributes may not be as tangible as we think - causal inference

Barsalou

(person); argued that concepts are unstable (against the defining attributes theory); the way people represent a concept changes as a function of the context in which it appears; 1. context-dependent information, 2. ad-hoc categories; e.g. 'frog' and 'eaten by humans' in French restaurant

category-based induction

Murphy and Ross (2010); inferences made about the behavior of an object based on the category that we have determined it belongs to

concept

a mental representation of a class of object or event; determines how things are related or categorized; allows us to decrease the amount of information we need to learn, perceive, remember, and recognize

basic-level

categorical level that is mid-level in descriptiveness; most common descriptor; e.g. apple

subordinate level

categorical level that is most specific; e.g. fuji apple

superordinate level

categorical level that is the most general; first level of a category; e.g. fruit

intension

distinguished by Frege (1952) as the set of attributes that define what it is to be a member of the concept

extension

distinguished by Frege (1952) as the set of entities that are members of the concept

ad-hoc categories

formed on the fly to achieve certain goals, e.g. 'things to sell at a garage sale'; evidence for the instability of categories within the defining attributes theory (against the theory)

cognitive economy

guides organization of information; we divide the world into classes of things so that we may decrease the amount of information we need to learn, perceive, remember, and recognize

defining attribute approach

holds that categories are represented as a list of features which are both necessary and sufficient; category membership is determined by checking in an item possesses all requisite features; e.g. Bachelor: it is necessary to be single, male, and an adult and having these attributes is sufficient to be a member of the category; evidence opposing this theory: 1. too clear cut; there are fuzzy concepts like temperature, 2. typicality gradient

context-dependent information

information used to incorporate into the representation of a concept for a certain situation so that the concept can be adjusted for context; evidence for the instability of categories within the defining attributes theory (against the theory)

category

mental representation of the relation of different concepts based on the structure of the world; has to do with the hierarchical relationship between concepts; three levels: superordinate, basic-level, and subordinate

categorisation

the process by which things are placed into groups called categories; results in efficient representations of the world; presumably includes process of abstraction or generalization; makes it possible to recognize a new object quickly

exemplar theory

theory that states that a category is represented by a list of previously encountered exemplars; new exemplars are compared to known exemplars; most similar items will influence clarification the most; instead of having a model that is a list of all characteristic features abstracted away from all members of the category, we store all instances that have been encountered in the past; best suited to complex concepts; evidence opposing this theory: 1. exemplar view depends on similarity, 2. does not easily provide an account for hierarchies

prototype theory

theory that states that categories are organized around a category prototype; potential members of a category are identified by how closely they resemble the prototype; categories under this theory are fuzzy; organized around typical properties or correlated attributes; category membership is similarity based; members share family resemblance; best suited to simpler concepts; evidence opposing this theory: 1. Hampton (1981): not all concepts have prototypic characteristics; abstract nouns like 'truth,' 2. Malt and Smith (1983): theory is incomplete as an account of the sort of knowledge that people have about concepts; people know about the relations between attributes rather than just attributes alone; some attributes are better indicators for a category than others, 3. people create categories on the fly without prototype; lack of attribute overlap