The Effects of Commercial Electronic Variable Message Signs ...

Method Ref. # Advantages Disadvantages
3.6.2 Fuel station, nearby mall
interviews
4.0 Safety Surrogate:
Laboratory
4.1 Driving simulator
4.1.1 Participant: selected,
sampled
4.1.2 Experimenter: remotely
present, unobtrusive
observation
4.1.3 Stimuli: simulated,
artificial; consistent, controlled
4.1.4 Responses: programmed
crash precursors; antecedent
participant and vehicle
behaviors; can have more
frequent events
4.1.5 Scenario: contrived route,
artificial; unnatural vehicle and
environment; safe from harm
36
4.2 Non-simulator laboratory 75
4.2.1 Pre-crash scenarios:
movies, pictures, acting out
4.2.2 Pre-crash reconstructions:
questionnaires, focus groups
161, 4,
70, 82
161, 4,
70, 82
161, 4,
70, 82
10, 82,
4
161, 4,
70, 82
5.0 Social Survey 14, 125
Relatively easy; less
resources.
58
Artificial, out-of-context testing
environment.
Know participant sample. Possible sampling bias.
More experimenter control. Possible artificial participant
behaviors.
Extremely repeatable
stimulus conditions.
Some control over nearcrashes;
can program more
frequent near-crash
opportunities.
Control over driving
scenario; participant safe
from harm.
160, 36 Relatively easy; less
resources.
36 Relatively easy; focus groups
more expensive.
5.1 Telephone survey Less resources; personal
interviewer; more flexible.
Artificial stimuli; hard to
simulate conspicuity and
legibility.
Lack of negative consequences
can unnaturally alter frequency
of near-crashes.
Unnatural vehicle and
environment; artificial scenario;
simulator sickness.
Artificial, out-of-context testing
environment; weak response
measure.
Artificial, out-of-context testing
environment; weak response
measure; focus group social
biases.
Out of context; opinions only;
more labor intensive; smaller
scale.