The Strategic Highway Investment Formula for Tomorrow (SHIFT) is the Kentucky Transportation Cabinet's data-informed approach for comparing capital improvement projects and prioritizing limited transportation funds. SHIFT 2022 incorporates advancements in methods and flexibility. This project revises the SHIFT crash data safety metric. The crash data safety metric from the previous version of SHIFT was excess expected crashes (EECs). It is computed using the total number of crashes of all severities. Locations with a higher proportion of severe (fatal and injury) crashes received the same weight as locations with an equal number of property damage only crashes. This project redefines the SHIFT crash data safety metric, increasing the weight of serious (KAB) crashes while still accounting for the potential to reduce less serious crashes. It also attends to the five-year and ultimate goals of Kentucky’s Strategic Highway Safety Plan by developing a metric sensitive to these policy goals. The five-year goal is represented by a new definition of EEC (the difference between expected crashes, the Empirical Bayes estimate, and the number of systemwide crashes when the goal is achieved). The ultimate goal is represented by the potential to reduce crashes on all road sections to zero, which is the EB estimate itself.
Digital Object Identifier
Souleyrette, Reginald; Tanzen, Riana; and Wang, Teng, "Incorporating Crash Severity and Continuous Improvement of SHIFT" (2023). Kentucky Transportation Center Research Report. 1767.