In recent years, joint count and fractional split model structure based approaches have emerged as a credible alternative for multivariate crash frequency dependent variables. However, current approaches in the fractional split theme have a limitation. The fractional split component of these frameworks allocates a proportion to all crash configurations. It is possible that, across spatial units, several crash configurations might have a large share of zero crashes. In the traditional multivariate context, in the presence of a high share of zeros, researchers employ zero-inflated or hurdle variants such as the zero inflated negative binomial model. The current research effort improves the fractional split based multivariate model systems with an explicit consideration for the potential presence of zeros by crash configuration. The newly included binary component can be employed to identify safer (or riskier) zones by crash configuration. The framework also accommodates unobserved heterogeneity across the components of the model system. The proposed model structure is estimated using zonal data from the Central Florida region, U.S., for 2016. The model considered six crash types—rear-end, angle, sideswipe, single-vehicle, multi-vehicle (three or more), and non-motorized crashes. The model estimation is conducted using an exhaustive set of independent variables. The model results clearly highlight the importance of accommodating zero crashes by crash type in the analysis. The model exercise is further augmented with a validation analysis.


    Access

    Download

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Enhanced Aggregate Framework to Model Crash Frequency by Accommodating Zero Crashes by Crash Type


    Additional title:

    Transportation Research Record: Journal of the Transportation Research Board


    Contributors:


    Publication date :

    2023-06-06




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English





    Analysis of fatal motorcycle crashes: Crash typing

    Preusser, David F. | Online Contents | 1995


    Crash involvement of drivers with multiple crashes

    Chandraratna, Susantha | Online Contents | 2006


    Aggregate crash prediction model based on gravity model: Introducing crash risk distribution concept

    Saman Dabbaghfeizi / Ali Naderan / Ali Tavakoli-Kashani | DOAJ | 2025

    Free access