John C. Foster

User performance and attitude towards schemes for alphanumeric data entry using restricted input devices

Abstract Results are reported from two usability trials in which a total of 14 schemes for alphanumeric data entry on television screens were evaluated. The seven schemes in the first trial used only the navigation and select keys on the TV remote control unit. The second trial used the best scheme from the first trial (slightly modified), a further six schemes using different combinations of the navigation and alphanumeric keys and a portable, infra-red keyboard. In both trials task completion rates and times were measured together with the number of keystrokes. User preferences were measured using attitude questionnaires and explicit ranking of the schemes. As expected, the keyboard was, overall, the best scheme-though not the most accurate. Where only a limited range of input keys were available, grid display schemes were preferred over menus and dynamic displays. Where an alphanumeric keypad was available on the remote control unit, a multiple press scheme was marginally preferred.

Please Mind the Doors — Do Interface Metaphors Improve the Usability of Voice Response Services?

Results are presented from an experiment to measure objective and subjective user responses towards three implementations of an automated voice response telephone service, two embodying rich implementations of metaphors in the service messages including appropriate sound effects to enhance realism, a third using a non-metaphorical presentation of standard menu prompts. It was found that task completion rates, navigation of the service and attitudes were all improved with the use of metaphors.