Evaluation of a Navigation Radio Using the Think-Aloud Method
Table 2
Successful completion with hints.
#
Task
Success
#
%
# Not do
1
Set destination to 100 north 5th avenue, Ann Arbor, MI.
9
69
2
Find the nearest McDonalds and set it as a waypoint.
8
62
3
Find the nearest gas station from the current position.
11
85
4
Cancel the route that you have set up.
10
77
5
Enter and set a destination to the main Detroit Airport.
12
92
6
Change map scale to zoom in slightly.
10
77
7
Enter and set a destination to 1600 Pennsylvania Ave, Washington DC.
10
77
8
Set the destination to the intersection of US-23 and I-94.
1
8
9
Set the destination to Cobo Hall in Detroit, MI.
9
100
4
10
Set the destination to intersection of Broadway St and Plymouth Rd, Ann Arbor.
9
100
4
11
Enter your home address and store it.
3
50
7
12
Insert the CD and select the third track.
13
100
13
Adjust volume to a comfortable level.
13
100
14
Tune FM radio to 91.7.
13
100
15
Adjust volume to a comfortable level.
13
100
16
Save the frequency as first preset.
6
46
17
Tune XM radio to Elvis station.
10
77
18
Turn off XM radio.
12
100
1
19
Change the time to 11:45 pm.
13
100
20
Connect the iPod and select the song “Wonderful Tonight.”
12
92
Note: under the heading success, # refers to the number of subjects out of 13 who successfully completed the task with hints. Thus, for task 1, 100 9/13 = 69%. The # Not Do refers to the number of subjects who were not asked to do up to four tasks to keep the experiment from taking too long. Thus, for task 9, only 9 of the 13 subjects performed the task, but all 9 of them (100%) complete the task.
