Mobile Intelligence

20.8 USABILITY EXPERIMENTS

We conducted a brief experiment to study the usability of the VOICE system and the Restaurant Search Guide. We selected 12 people to participate, none of whom had any prior experience with the VOICE system. We gave each participant a set of instructions outlining their goals, as well as the tasks required to complete each goal. Each of the participants used VOICE to enter specific queries and retrieve the results. The participants' goals were

1. to find a take-out Chinese restaurant in the 06082 ZIP code area and get the phone number for this restaurant and
2. to find an eat-in Italian restaurant in the 06082 ZIP code area and get directions to this restaurant.

Each participant worked by themselves using only a mobile phone, and all of their attempts were logged electronically. After the experiment, we asked each of the participants to fill out a questionnaire, which included some biographical questions as well as questions to evaluate their experience with VOICE:

1. To what extent did the VOICE system understand what you said?
2. To what extent was the VOICE system's speech easy to understand?
3. To what extent did you understand what to say at each of the prompts?
4. Were you able to complete the tasks and get the information that you required?
5. After using VOICE, how likely are you to use a similar system in the future?

The questions were answered on a five-point Likert scale, where 1 indicated never, unlikely, or very difficult, and 5 indicated always, likely, or ...