Multilevel Mixed-Effects Models to Identify Contributing Factors on Freight Vehicle Crash Severity

Freight vehicle crashes are more serious than regular because they likely to lead major damage and injury once occur; therefore, countermeasures needed. The fatality rate from freight is 1.5 times higher that of all other accidents, the death expressway continues increase. In this study, ten-freight-vehicle crash severity models (the ordered logit probit model, multinomial mixed-effects random-effects multilevel model) used analyze factors. model was constructed using data collected expressways over eight years, 13 factors were derived increase 7 reduce crashes. As a result comparing 10 AIC BIC, showed best performance. It expected it can contribute improving safety vehicles in section by utilizing related study.