  The pattern of pedestrian crashes varies greatly depending on lighting
circumstances, emphasizing the need of examining pedestrian crashes in various
lighting conditions. Using Louisiana pedestrian fatal and injury crash data
(2010-2019), this study applied Association Rules Mining (ARM) to identify the
hidden pattern of crash risk factors according to three different lighting
conditions (daylight, dark-with-streetlight, and dark-no-streetlight). Based on
the generated rules, the results show that daylight pedestrian crashes are
associated with children (less than 15 years), senior pedestrians (greater than
64 years), older drivers (>64 years), and other driving behaviors such as
failure to yield, inattentive/distracted, illness/fatigue/asleep. Additionally,
young drivers (15-24 years) are involved in severe pedestrian crashes in
daylight conditions. This study also found pedestrian alcohol/drug involvement
as the most frequent item in the dark-with-streetlight condition. This crash
type is particularly associated with pedestrian action (crossing
intersection/midblock), driver age (55-64 years), speed limit (30-35 mph), and
specific area type (business with mixed residential area). Fatal pedestrian
crashes are found to be associated with roadways with high-speed limits (>50
mph) during the dark without streetlight condition. Some other risk factors
linked with high-speed limit related crashes are pedestrians walking
with/against the traffic, presence of pedestrian dark clothing, pedestrian
alcohol/drug involvement. The research findings are expected to provide an
improved understanding of the underlying relationships between pedestrian crash
risk factors and specific lighting conditions. Highway safety experts can
utilize these findings to conduct a decision-making process for selecting
effective countermeasures to reduce pedestrian crashes strategically.
