Author(s)

Maroa Mumtarin, Skylar Knickerbocker, Theresa Litteral, Jonathan S. Wood

Department of Civil Construction and Environmental Engineering, Iowa State University, Ames, USA.

This study develops a procedure to rank agencies based on their incident responses using roadway clearance times for crashes. This analysis is not intended to grade agencies but to assist in identifying agencies requiring more training or resources for incident management. Previous NCHRP reports discussed usage of different factors including incident severity, roadway characteristics, number of lanes involved and time of incident separately for estimating the performance. However, it does not tell us how to incorporate all the factors at the same time. Thus, this study aims to account for multiple factors to ensure fair comparisons. This study used 149,174 crashes from Iowa that occurred from 2018 to 2021. A Tobit regression model was used to find the effect of different variables on roadway clearance time. Variables that cannot be controlled directly by agencies such as crash severity, roadway type, weather conditions, lighting conditions, etc., were included in the analysis as it helps to reduce bias in the ranking procedure. Then clearance time of each crash is normalized into a base condition using the regression coefficients. The normalization makes the process more efficient as the effect of uncontrollable factors has already been mitigated. Finally, the agencies were ranked by their average normalized roadway clearance time. This ranking process allows agencies to track their performance of previous crashes, can be used in identifying low performing agencies that could use additional resources and training, and can be used to identify high performing agencies to recognize for their efforts and performance.

Traffic Incident Management, Roadway Clearance Time, Performance Measures and Ranking, Agency Performance Evaluation, Tobit Regression Model

Mumtarin, M. , Knickerbocker, S. , Litteral, T. and Wood, J. (2023) Traffic Incident Management Performance Measures: Ranking Agencies on Roadway Clearance Time. Journal of Transportation Technologies, 13, 353-368. doi: 10.4236/jtts.2023.133017.