Tuesday, 26 March 2019, 7:17 PM
Site: Learning Management System
Course: 601393 - Human Computer Interaction Course File (603393CF-11)
Glossary: hci g

problem solving

Searching through a problem space from a known start state to a desired end state, or one of a set of desired end states, applying operators of uncertain outcome to move from state to state. Problem solving typically refers to a path through the problem space that includes explorations of deadend paths and backing up to prior states. (see skilled behavior for a contrasting type of behavior)

problem space

A mental representation of a problem, including the start state, the goal state, and the operators or moves that allow transitions between states. According to Newell and Simon’s (1972) theory of problem solving, humans solve problems by constructing and searching a problem space.

procedural knowledge

Also called “how to do it” knowledge. The knowledge of which operators to perform to move from a known start state to a desired state in a problem space.

Production system

A programming language made up of conditional statements. If all conditions are satisfied, then action is taken.


In cognitive-dimensions analysis, a statement of what is required (in cognitive-dimensions terms) to support a given generic activity. The profile of an activity states for each cognitive dimension whether that dimension is material and, if so, what value it should have (e.g., for modification, viscosity must be low, visibility must be high, etc.).

progressive evaluation

In the cognitive-dimensions framework, the ability to review or test a partially complete structure, to check on progress to date it is important for novices, and becomes less so as one gains experience. Some systems allow only a complete design to be reviewed; others allow a review at any stage.

propagation of representations

A component of information-processing activity in which sequences of transformations from one representational form (or medium) to another result in information-processing activity. Hutchins claims that “representational states are propagated from one medium to another by bringing the states of the media into coordination with one another” (1995a, 117).

propositional representations

Representations that have a more-or-less arbitrary structure; for example, a word or a sentence in a natural language. See also analog representations.


an operational model of a design or software development proposal, usually created for testing and feedback purposes