An Empirical Analysis on Temporal Stability of Factors in Work Zone Crashes in Florida: A Random Parameters Heterogeneity-in-Means Approach

Work-zone crashes in Florida have increased recently, particularly from 2012 to 2017. This study investigates on the factors leading to work-zone crashes in Florida in two distinct economic time periods in Florida—recession-induced period (2012–2014) and the post-recession period (2015–2017). The main focus of this study is to estimate two separate time period models focusing on injury severity of work zone related crashes with the application of mixed logit model incorporated with a heterogeneity-in-means approach. The variables extracted from Crash Analysis Reporting system in Florida encompasses a wide variety of factors related to crash, vehicle, roadway geometry, traffic volume, driver demographics, and spatial and temporal characteristics that affect the injury severity of work zone crashes. The model results indicate that significant temporal instability resulting from a possible complex interaction with macroeconomic conditions over the years from larger scope and higher budgeted work zone projects in Florida with evolving driving behavior, traffic volume and crash reporting practice in traditional state crash data management. Mixed logit models on injury severity with heterogeneity-in-means approach on work zone crashes open a promising frontier of future research.