Stephen V. Burks

Playing both roles in the trust game

This paper examines the effect of subjects playing both roles in a trust game. We compare two information treatments to our replication of the single-role trust game. The treatments alter the point at which participants are told they will play both roles. We find that playing both roles reduces both trust and reciprocity. We also explore relationships between demographic and personality characteristics and decisions in the game. We find that a social-psychological measure of Machiavellian behavior predicts distrust but not a lack of trustworthiness, and that non-white participants trust less in a predominantly white environment, but are no less trustworthy.

Obesity is associated with the future risk of heavy truck crashes among newly recruited commercial drivers

This study estimates the dose-response relationship between body mass index (BMI) and crash risk in operators of heavy commercial motor vehicles. Intake data were collected during the first two weeks of instruction from 744 new truck drivers training for their commercial drivers licenses at a school operated by the cooperating trucking firm. Drivers were then followed prospectively on the job using the firms operational data for two years, or until employment separation, whichever came first. Multivariate Poisson regression and Cox proportional hazards models were used to estimate the relationship between crash risk and BMI, controlling for demographic characteristics and for variations in the exposure to risks on the road. Results from the Poisson regression, which used cumulative miles driven as an exposure control, indicated that compared to normal BMI (18.5<BMI<25) the risk ratio (RR) for all crashes was significantly higher for drivers in the combined obesity Classes II and III: RR=1.55 (95% CI 1.24-1.94). Similarly, the multivariate Cox proportional hazard model (controlling for miles and job type on a week-by-week basis) showed that crash risk was significantly higher compared to normal BMI for the same combined obesity Classes II and III: RR=1.54 (95% CI 1.13-2.10). The results of this prospective study establish an association between obesity and crash risk and have important implications for driver health and public safety.

Attitudes of Truck Drivers and Carriers on the Use of Electronic Logging Devices and Driver Harassment

The research contained herein is an examination of managerial harassment experienced by drivers, and whether harassment is associated with the method used to log hours of service (HOS). Similar information was gathered from a sample of carriers. Truck drivers were interviewed in person at truck stops in the United States; carriers were interviewed online via a Web survey. The evidence in this survey research does not support concluding that harassment occurs due to being in a situation where HOS are logged using electronic logging devices (ELDs).

Driver Selection Tests and Measurement

This report synthesizes current information on driver selection methods of commercial truck and bus companies, based primarily on the use of tests, measurements, and other assessments of applicants. It identifies and describes driver selection methods and instruments and their usefulness in predicting driver safety. The audience for this study includes motor carrier safety managers, other carrier executives and managers, and government and industry officials. The report reviewed the academic, commercial, and industrial literature on tests, measurements, and other procedures used by motor carriers to select safe commercial drivers. The study revealed large and enduring individual differences in crash risk among commercial drivers and highlighted the need for valid and usable driver selection procedures for carriers. Sources of this information were naturalistic driving studies, behavioral histories (“biodata”), driving behavioral histories, and other human performance studies, as well as federal regulations. Surveys and interviews were used to obtain information from motor carrier safety managers and other experts on selection procedures and tests and on underlying driver characteristics relevant to risk. The project surveys of motor carrier safety managers and other experts on truck and bus safety were convenience samples of individuals active in national industry and research organizations. These individuals included professionals in government, industry trade associations, other industry roles (e.g., safety consulting), and research. These survey respondent groups of interested, knowledgeable individuals provided indications of industry thinking on safety management questions from two different perspectives. A select group of ten motor carrier safety managers—those whose questionnaire responses indicated an active focus on driver assessment—were interviewed for case studies on driver selection practices. Each case study describes the company’s driver selection methods and features innovative hiring and related human resources management practices.

Safety Management in Small Motor Carriers

The goals of this synthesis were to identify (1) useful practices for safety management in small companies and (2) a logical and practical progression to more active and comprehensive safety management for small companies as they grow. The report explores small motor carrier strengths and weaknesses and identifies potentially effective safety practices. It found that each company’s safety outcomes are more reflective of its own safety practice and operating environment than whether it is large or small. The audience for this study includes small motor managers, as well as government and industry officials. This report reviewed research on motor carrier safety, safety management, and organizational management, in general. Literature review searches were performed using websites, academic databases, books, trade press publications, and articles. In addition, members and friends of TRB Truck and Bus Safety and Trucking Industry Research Committees, FMCSA Analysis Division, and the U.S.DOT Volpe National Transportation Systems Center provided materials. The project survey of five truck and bus industry trade associations’ members was a convenience sample of individuals judged qualitatively to best represent the target population and whose support was critical to the success and validity of the work. Organizations included the American Bus Association (ABA), Bus Industry Safety Council (BISC), National Association of Small Trucking Companies (NASTC), Owner–Operator Independent Drivers Association (OOIDA), and the United Motorcoach Association (UMA). These survey respondent groups (112—79 truck and 33 bus) of interested, knowledgeable individuals provided indications of industry thinking from different perspectives. A select group of ten small motor carriers’ were interviewed for confidential case studies on safety management problems and practices. These ten provided substantial information on innovative small carrier safety practices.