Geographical Information Systems-Based Spatial and Statistical Investigation to Enhance Transportation Safety for the Aging Population
Ulak, Mehmet Baran (author)
Ozguven, Eren Erman (professor directing dissertation)
Vanli, Omer Arda (university representative)
Moses, Ren (committee member)
Sobanjo, John Olusegun, 1958- (committee member)
Spainhour, Lisa (committee member)
Florida State University (degree granting institution)
FAMU-FSU College of Engineering (degree granting college)
Department of Civil and Environmental Engineering (degree granting department)
Traffic crashes are one of the leading causes of death, substantial economic loss, and severe injuries for drivers. They also put lives of people at risk, cause severe traumas and incapacitating injuries, which usually require a painful healing process. Over the last 25 years, many researchers have recognized the necessity of delving into the nature of the traffic crashes. This necessity arises from the fact that developing methodologies to reduce crashes is vital to provide the public with safe and reliable transportation. From a transportation safety perspective, this problem becomes even more challenging and complex when aging populations are considered due to their cognitive, behavioral, and health limitations. Moreover, the number of aging road users and crashes involving aging drivers on Florida roadways are expected to increase in the near future due to their growing population in the state, which makes studies on aging population-involved crashes even more critical. With this motivation, unlike previous crash-focused traffic safety studies mostly focusing on the general population, this dissertation attempts to understand the unique nature of aging population-involved (aging-involved) crashes. Note that by "aging-involved", the crashes involving at least one 65 years and older individual are meant in this dissertation. The utmost importance is given to answering the following question: How do the aging-involved crashes vary compared to other age group-involved crashes? Given the limitations of existing traffic crash studies on addressing the needs of aging populations, this dissertation proposes several novel methodological approaches with the following objectives: • to discover the geo-spatial differences between aging- and other age group-involved crashes based on the comparison of high risk crash locations, • to identify the statistically significant factors influencing the aging-involved crashes using a multiple binary choice model-based approach, • to disclose the differences between crashes involving 50-64 and 65+ drivers in terms of involvement characteristics, spatial distribution, and significant factors causing those crashes, • to stratify the aging drivers by dividing them into three subgroups (65-69, 70-74 and 75+) in order to explore the differences among aging drivers, who are oftentimes evaluated as a homogeneous group, • to provide a spatiotemporal comparative investigation of the crashes involving aging drivers, passengers, bicyclists, and pedestrians, • to determine the factors that drive both the crash occurrence probability and the crash rate of aging drivers, passengers, bicyclists, and pedestrians, • to understand where and how far away people have crashes compared to where they live, and what the statistical nature of proximity of crash spots to the residence locations of crash occupants is. To the authors' knowledge, such a comprehensive investigation of aging population-involved crashes has not been conducted previously in the traffic safety field, which represents the novel contribution of this work. For this purpose, several methodological approaches were applied on both different counties in the State of Florida as well as the whole state. Aging-involved crashes were spatially and temporally investigated using GIS-based methodologies in order to discover the significant factors that affect those crashes using statistical modeling approaches. The most important findings of this work can be summarized as follows: • Aging-involved crashes differ from other age group involved crashes both spatially and temporally. • Aging-involved crash density maps have a unique geo-spatial pattern, which is different than the patterns of other age groups' crash density maps. • Spatial distributions of aging adults and aging-involved crashes are strongly correlated as indicated by the population factor approach. • Aging drivers in different age cohorts such as 65-69, 70-74, and 75+ do not constitute a homogeneous group and rather heterogeneous in terms of crash involvement. • There are significant differences in the effect of significant causal and spatiotemporal factors on the crash involvement not only between 65- and 65+ drivers, but also between stratified age groups of 65+ drivers. • Significant spatiotemporal variations in crash rates of different types of aging roadway users (e.g. driver, pedestrian, etc.) were captured. • Traffic safety of 65+ population compel spatially and temporally tailored remedies in order to address issues emerge at different roadway segments at weekdays and weekends. • Facility variables such as health facilities, religious facility, and supermarkets are highly influential on 65+ crashes, and hence roadways around these facilities should be particularly scrutinized by road safety stakeholders. • High aging-involved crash rate roadways are found to vary spatially depending on whether it is weekday or weekend. • The information obtained from crash spot –residence location proximity analysis can help in developing methodologies that can integrate population into crash frequency prediction methods.
Aging, GIS, Human Factors, Spatial Analysis, Statistical Analysis, Traffic Safety
October 26, 2018.
A Dissertation submitted to the Department of Civil and Environmental Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy.
Includes bibliographical references.
Eren Erman Ozguven, Professor Directing Dissertation; Arda O. Vanli, University Representative; Ren Moses, Committee Member; John O. Sobanjo, Committee Member; Lisa Spainhour, Committee Member.
Florida State University