  This study investigates the potential effects of different Dynamic Message
Signs (DMSs) on driver behavior using a full-scale high-fidelity driving
simulator. Different DMSs are categorized by their content, structure, and type
of messages. A random forest algorithm is used for three separate behavioral
analyses; a route diversion analysis, a route choice analysis and a compliance
analysis; to identify the potential and relative influences of different DMSs
on these aspects of driver behavior. A total of 390 simulation runs are
conducted using a sample of 65 participants from diverse socioeconomic
backgrounds. Results obtained suggest that DMSs displaying lane closure and
delay information with advisory messages are most influential with regards to
diversion while color-coded DMSs and DMSs with avoid route advice are the top
contributors impacting route choice decisions and DMS compliance. In this
first-of-a-kind study, based on the responses to the pre and post simulation
surveys as well as results obtained from the analysis of
driving-simulation-session data, the authors found that color-blind-friendly,
color-coded DMSs are more effective than alphanumeric DMSs - especially in
scenarios that demand high compliance from drivers. The increased effectiveness
may be attributed to reduced comprehension time and ease with which such DMSs
are understood by a greater percentage of road users.
