Identifying characteristics that impact motor carrier safety using Bayesian networks

Application of a Hurdle Model with Random Effects to Explore the Relationship between Operational Characteristics and Safety Performance

“…In relation to the need for more accurate data and the issue of potential omitted variables, the MCMIS serves as a good example. The MCMIS, maintained by the Federal Motor Carrier Safety Administration ( 66 ), synthesizes datasets providing information on crash, census, inspection, and safety profiles of motor carriers, which has enabled and benefited several studies examining factors affecting motor carrier safety performance, producing valuable insights ( 10 – 13 , 16 ). It is then recommended that state-wide or nationwide efforts be devoted to collecting relevant information and forces be joined together to link datasets from different sources to establish a more comprehensive database to empower future research ( 16 ).…”

“…Chen (12) identified similar findings, adding that small companies (defined by the number of trucks) were less likely to achieve satisfactory safety ratings than their large counterparts, probably as a result of a lack of resources to invest in technology and equipment or to implement sound safety practices to ensure safe operations (8). On the other hand, Hwang, Boyle (13) identified no direct relationship between fleet size (defined by the number of power units) and safety ratings, while Mooren et al ( 14) compared the claim rates per truck for higher claiming, large companies (with more than 14 trucks) and found that companies with larger fleets had a higher mean claim rate than companies with smaller fleets. The effect of journey distance has been examined in relation to its effect on driver fatigue (15) as well as the implications of the traveling environment (urban or non-urban) (10), both of which have been shown to affect fleet safety.…”

“…However, the relationship identified was not as straightforward. Passenger carriers were found to have significantly better safety performance/ rating than the other carrier segments, with different relationships with safety rating identified for passenger and other carrier segments (13,16). Other factors of specific interest to certain studies include financial status (17), union membership (16), deregulation, fleet age, service type, and mechanical failure rate (5).…”

“…( 16 ) and Moses and Savage ( 10 ) found that for-hire carriers had significantly poorer safety performance than private carriers while Chen ( 12 ) stated that for-hire companies were more likely to receive satisfactory safety ratings than private ones. The number of traffic violations was found to be associated with safety performance ( 5 ) and safety rating ( 13 ). However, the relationship identified was not as straightforward.…”

“…Another potential limitation of this study is the omitted variable biases. Factors including organizational financial performance (17), driver characteristics (number of drivers [13], driver/non-driver ratio [5], ratio of young/older drivers [63], driver traffic violations [5,13]), and bus configuration (3,64,65) may also influence operators' safety performance and should be examined in future research.…”