, multiple-tank-car release incident. Previous studies exclusively assumed that railroad tank car
releases in the same train accident are mutually independent, thereby estimating the number of tank cars
releasing given the total number of tank cars derailed based on a binomial model. This paper specifically
accounts for dependent tank car releases within a train accident. We estimate the number of tank cars
releasing given the number of tank cars derailed based on a generalized binomial model. The generalized
binomialmodel provides a significantly better description for the empirical tank car accident data through
our numerical case study. This research aims to provide a new methodology and new insights regarding
the further development of risk management strategies for improving railroad crude oil transportation
safety.