Related Experiment Video
Updated: Aug 15, 2026

An Instrumented Pull Test to Characterize Postural Responses
Published on: April 6, 2019
Job change rate as a crash predictor for interstate truck drivers
Loren Staplin1, Kenneth W Gish
1TransAnalytics, LLC, Kulpsville, PA 19443, USA. lstaplin@transanalytics.com
Abstract:
This research analyzed the Motor Carrier Management Information System (MCMIS) database to develop estimates of the increased risk of crash involvement experienced by commercial drivers who change jobs frequently. These analyses quantified the risk of single- and multiple-crash involvement as a function of annual job change rate, and expressed the relative risk for drivers with more versus fewer job changes through calculation of the "odds ratio" statistic. Significant odds ratio values were found, indicating that crash risk begins to rise when a driver has averaged more than two jobs with different employers each year for 2 years or longer, and that the odds of being involved in multiple crashes more than doubles for drivers with three or more jobs per year during this same interval. Opportunities for further research, focusing on variables that could be extracted from existing data sources to further enhance the validity and predictive value of the relationships found in this study, were also identified.
Related Concept Videos
Introduction to Test of Independence
The test statistic for a test of independence is similar to that of a goodness-of-fit test:
Hypothesis Test for Test of Independence
H0: The two variables (factors)...
Determination of Expected Frequency
Hazard Rate
Hazard Ratio
For example, in a clinical trial evaluating a...
Application of Rates of Change

