The Effects of Commercial Electronic Variable Message Signs ...

Variable Ref. # Advantages Disadvantages
2.6.2 Entertainment: radio;
CD player
2.6.3 Auditory/vocal: voice
actuated
3.0 Driver Attention /
Distraction
48, 24,
54
3.1 Objective measures 129
3.1.1 Eye glance behavior:
eye movements; number of
glances; duration of
glances; glance object
3.1.2 Distractor
performance; secondary
task
Secondary distractor.
154 Low probability of
occurrence.
79, 113,
32, 146,
145
129, 42,
125, 53,
160, 83,
161, 78
Excellent measure of
unconscious attention /
distraction.
83, 53 Excellent measure of
distraction.
3.1.3 Visual occlusion 15 Good measure of
distraction.
3.1.4 Feature detection 48
3.1.5 Feature recognition 48 Good measure.
3.1.6 Driver workload; task
performance
38, 15,
113
Excellent indicator of
distraction.
50
Delicate, expensive
equipment. Difficult to
calibrate. Expensive to
analyze data.
Can increase risk in field
experiments. Can be
artificial.
Can increase risk in field
experiments. Unnatural
driving task.
Complicated to measure.
3.1.7 Head turning 78 Easy to measure. Less important.
3.1.8 Driver errors 83 Excellent measure of
distraction.
3.1.9 Reaction time;
perception-reaction time
3.2 Inferred measures
3.2.1 Surprise; orienting
response
15 Good indicator of
distraction.
Many varieties. Low
probability of occurrence.
Difficult to measure.
Difficult to measure.