A term in a notational system or other information artifact that is defined with reference to the primitive concepts of the system, or with reference to other abstractions that are ultimately defined by primitives. It is frequently used to aggregate many instances, so that all can be manipulated by a single action; thus, a heading style is a typical word-processor abstraction defined in terms of font properties, and all its instances can be altered by altering its definition.
A hierarchical description of the functional structure of a work domain, in which work-domain purposes are related to underlying physical structures. Also referred to as a structural means-ends hierarchy because links between adjacent levels connect ends (upper nodes) to means (lower nodes).
The latest in a series of computational cognitive architectures developed by John Anderson and colleagues. ACT-RPM contains architectural mechanisms for cognitive, perceptual, and motor performance and learning. It was one of the architectures reviewed in Pew & Mavor (1998). More information about this series of architectures can be found in Anderson (1976, 1983, 1993) and Byrne & Anderson (2001).
A lower level of organization in human endeavor, including simple gestures and other motor behavior.
The significant and typically collective endeavors of humans. It is the fundamental concept in activity theory, which conceives of activity as conducted through individual actions and mediated by artifacts. In the cognitive-dimensions framework, an activity is likewise a significant endeavor conducted through individual actions, but six generic types of activity are distinguished (e.g., search, design, etc.); at present, only individual interaction with information artifacts is considered.
adaptationism, adaptationist approach
The thesis that selection pressures have been the most powerful cause of evolution; a useful methodological heuristic is to assume that biological and behavioral structures are the results of adaptation to the environment.
Perceptual characteristics of an object that make it obvious what the object can do and how it can be manipulated.
According to the theory of James J. Gibson, these are directly perceived possibilities for action in the environment.
Representations that share the structure of the things they represent. For example, a picture is an analog representation. See also propositional representations.
usability evaluation based on a careful analysis or theoretical modeling of user interface features, usually carried out by usability experts
The investigation of social structure, social relationships, and individual social action through an emphasis on culture—originally “other cultures” but increasingly the emphasis is on “home” cultures.
considering machines (especially computers) as if they have human capabilities or responsibilities
A computational architecture using resource scheduling and reactive planning (techniques from artificial intelligence). More information can be found in Freed (1998). It has been used as a GOMS modeling tool (John, 2002; Remington, et al., 2002).
A diverse class of human-created systems, applications, tools, and conventions, including language and mathematics, that mediate human activity. Artifacts are the products of prior human activity; they both enable and constrain current human activity, and their use helps to orient the design of future artifacts. An information artifact (as used in the cognitive-dimensions framework) is an artifact designed to store, create, present, or manipulate information, whether noninteractive (e.g., a book or a map) or interactive (e.g., a spreadsheet or a heating controller).
automatic cognitive processes
Processes that are relatively quick and effortless, requiring little attention or monitoring. Well-practiced skills, like walking and driving, or signing one’s name, are examples of automatic cognitive processes. See also controlled cognitive processes.
an icon or other visual depiction used to represent the user in an information display