Definitions

Competitive analysis - A usability evaluation in which two or more competing products are compared.

Contextual inquiry - Observation of product use in a field environment. The observer engages in a dialog with the product user.

Cost/benefit modeling - Use of mathematical models to predict the financial impact of various types of usability activities.

Ethnographic observation - Unobtrusive observation of product use in a field environment. The user is usually not aware that he/she is being observed.

Focus groups - Moderated group discussion focused on several issues. Used extensively in market research.

Interactive voice response (IVR) - A speech-based user interface in which the user listens to spoken messages and responds with key-presses or spoken commands.

Task analysis - A process in which task structure is analyzed. Critical elements and potential usability issues are identified. Precedes user interface design.

Usability inspection - Refers to several methods in which usability specialists review the design of a static or dynamic prototype. Product users are not involved. The most frequently used inspection method is heuristic evaluation.

Usability testing - Generic term for a usability evaluation involving use of a prototype or product by its intended user. In a collaborative usability test the usability specialist carries on an active dialog with the product user in order to better understand his/her behavior and opinions. In a performance-based usability test the emphasis is on assessing user performance in relation to specific goals.