摘要: |
Teen novice drivers are well known to have higher crash rates than other age cohorts. A major safety question that lacks clarity and definitive scientific evidence is whether teen drivers who are exposed to greater diversity of traffic and road environments early in their driving careers have lower crash involvement than those who are exposed to less diversity. Ideally, this question would be addressed by analyzing how driving exposure, both the amount of driving (i.e., exposure) and driving conditions (i.e., road environment and geometry), changes when teens make the transition from supervised to unsupervised driving. Existing data collected for the Second Strategic Highway Research Program (SHRP2) Naturalistic Driving Study (NDS) offer the opportunity to investigate this research question. While supervised driving data are not available in the SHRP2 NDS, it is possible to compare the diversity of experience in the early months of unsupervised driving with later months. This would allow for empirical examination of the association of exposure to greater diversity with crashes and near-crashes.
The overall objective of this research is to use the SHRP2 NDS data, and other potential naturalistic driving data sources, to evaluate how exposure to driving in more diverse traffic and road environments is associated with teen driver behavior, performance indicators that lead to crashes, and safety surrogate measures (e.g., near-crashes, speeding, observed distracted driving). The analysis should consider changes in driver behavior and subsequent crash risk. Based on the results of the analysis, the study will develop recommendations/strategies for improving teen driver safety.
The period of early exposure during unsupervised driving will be the focus of the proposed research. A research hypothesis will be that teens who spend a greater amount of either time or miles driving in a wider range of environments in their first 6 months of unsupervised driving are significantly less likely to experience a crash or near-crash event in each subsequent 6 months of experience, compared to teens with a more limited/restricted range of experience in their first 6 months of unsupervised driving. If it is found that not enough participants were enrolled in the NDS during their first 6 months of driving experience, this hypothesis may be modified to use the first 12 months of driving experience as the reference interval. |