SPOKEN HELP FOR A CAR STEREO - AN EXPLORATORY-STUDY

This paper reports an investigation of the use of spoken (audible) hel p in an attempt to increase the usability and learnability of a high-e nd car stereo. To investigate the usefulness of audible spoken help fo r a car stereo, a simulation was constructed within which experimental help systems were incorporated. To validate the simulation, the 'real ' car stereo (an existing consumer product, acting as the control cond ition) was compared empirically with its simulation. An experiment, us ing the four conditions of actual product, simulation of actual produc t, and two simulations employing different spoken help functions was u ndertaken. Forty participants in a between subjects design, carried ou t specified tasks with the car stereo version according to experimenta l condition. User performance, specifically task completion and number of button presses, and subjective reactions were measured. The simula ted spoken help versions clearly assisted users with their tasks, and, in general, were responded to favourably when compared to performance with the control simulation and its product equivalent. This explorat ory study provided further insight into users' concerns about car ster eo usability and the overall results revealed the potential of spoken help facilities for novice users. We can conclude that the use of audi ble, spoken help, whether as a global option or as a specific 'button help', enhances the performance of, and is acceptable to, novice users of this consumer product type. Finally, this investigation also demon strated that the use of a (Hypercard) simulation versus the 'real' cou nterpart (the simulated car stereo) to be generally valid and appropri ate for this type of evaluation. In order to progress this direction, examination of the design of spoken help dialogues, user control of th ese, and issues concerning 'longitudinal' use of the product type are recommended.