Computer-Mediated Communication / Computercommunicatie A Master IK, CIW, MMI L.M. Bosveld-de Smet Hoorcollege 2; ma. 11 sept. 2006;

Human-computer interaction: terminology In Glossary of Computing Terms  Computer system = complete collection of components (hardware, software, peripherals, power supplies, communication links) making up a single computer installation  Interface (in machine architecture) = hardware and associated software needed for communication between processors and peripheral devices, to compensate for the difference in their operating characteristics (see bus interface, interface board or card, …)  (User) interface (in hci, also called user environment) = a way for communication between the user and the computer  User interface = made up by the combination of those parts of the hardware and software of a system with which the user interacts

Human-computer interaction: terminology Faulkner (1998): human-computer interface:  mediates between user and computer system  protects users from harsh realities of system  reflects system model to users  translates users’ intentions into appropriate system activity

User interfaces Are described in a variety of ways, whose names highlight their main features  graphical user interface  menu selection interface  windows environment  forms dialogue  ….

Appropriate user interfaces Choice of appropriate user interfaces depends on:  amount of information to be presented or elicited  experience of the users  familiarity of the particular software

Railway sites Dutch Railways Belgian Railways German Railways British Railways French Railways

Testing railway sites Interaction models:  Norman  Abowd & Beale Interaction styles Goal-oriented testing  tasks  interface actions

Results testing railway sites Railway sites  Interaction styles Dix et al. (2004) Command line Menus Natural language Question/answer Query dialog Form-fills Spreadsheets WIMP Point and click D interfaces -----

Notable features Extras Dutch site:  autocompletion station names  quick and advanced search Characteristic German and French site:  guide users stepwise through journey planning process British site:  only form-fill for buying ticket  worst appreciated site

Menus Attractive alternatives to direct-manipulation strategies:  menu selection  form fillin Modern menus:  pulldowns  check boxes  radio buttons in dialog boxes  embedded links in web pages

Effective menus Menus elicit user recognition Menu items can be  textual  graphic  auditory Complex menus should be carefully designed Primary goal:  relevancy to users’ tasks

Menus: design issues Task-related organization Phrasing of items Sequence of items Graphic lay-out and design Response time Shortcuts for knowledgeable frequent users Online help Error correction Selection mechanisms

Menu design Remember: there is no perfect menu structure There are some guidelines

Menu Selection Guidelines (1) Use task semantics to organize menus  single, linear sequence, tree structure, acyclic and cyclic networks Prefer broad-shallow to narrow-deep Show position by graphics, numbers, or titles Use items as titles for subtrees Group items meaningfully Sequence items meaningfully

Menu Selection Guidelines (2) Use brief items, begin with the key word Use consistent grammar, layout, terminology Allow type ahead, jump ahead, or other short cuts Enable jumps to previous and main menu Consider online help; novel selection mechanisms; and optimal response time, display rate, screen size