THE ROLE OF INSTRUCTION SETS IN OPERATOR SATISFACTION WHILE USING A VOICE ACTIVATED DIALING SYSTEM

The role of setting user expectations (with different instruction sets ) in operator satisfaction while using a voice activated dialing syste m (VADS) was investigated during simulated driving. The VADS itself wa s simulated using Wizard-of-Oz techniques. Sixteen subjects in two ins truction set groups (brief and extended instructions) participated, wi th four males and four females in each group. The instruction sets wer e identical except for the addition of an example demonstrating that t he VADS may require the user to repeat themselves before being underst ood. There were seven different tasks requiring interaction with the V ADS. Voice recognition accuracy was varied between the two sessions (5 0% and 83%). All tasks were performed under highway driving conditions in a driving simulator. Subjects were required to fill out a user sat isfaction survey after each session. On a microscopic level, the resul ts showed that there was no significant difference in user satisfactio n levels between the two accuracy conditions for subjects receiving th e extended instruction set while those receiving the brief instruction set showed significantly higher satisfaction with the 83% accuracy co ndition. Additionally, the results showed users are more likely to pur chase a VADS given the extended instruction set (expectations). This h as implications on a macroscopic level for the VADS producers and dist ributors.