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Published on: January 20, 2023
A comparative analysis of freeway crash incident clearance time using random parameter and latent class hazard-based
Naima Islam1, Emmanuel K Adanu2, Alexander M Hainen1
1Dept. of Civil, Construction and Environmental Engineering, Univ. of Alabama, P.O. Box 870288, Tuscaloosa, AL 35487-0205, United States.
Understanding freeway incident clearance times is crucial for traffic flow. The latent class model better explains factors influencing these durations compared to random parameters modeling, aiding policy decisions.
Area of Science:
- Transportation Engineering
- Econometrics
- Traffic Management
Background:
- Freeway incident clearance times significantly impact traffic flow and have substantial economic consequences.
- Understanding factors influencing incident duration is critical for effective traffic management.
Purpose of the Study:
- To investigate factors affecting freeway incident clearance times in Alabama.
- To compare the performance of random parameters duration modeling and latent class duration modeling in explaining incident durations.
- To identify the most suitable econometric model for analyzing unobserved heterogeneity in incident clearance times.
Main Methods:
- Utilized a unique dataset of 2206 freeway crash incidents from Alabama in 2018.
- Applied advanced econometric methods: random parameters duration modeling and latent class duration modeling.
- Integrated data from multiple sources including ALDOT, CAPS, ASAP, and HPMS.
Main Results:
- The random parameters model identified 19 statistically significant variables (5 random, 14 fixed).
- The latent class model identified 18 statistically significant variables across two distinct classes (23% and 77% probability).
- The latent class model demonstrated a superior fit for the incident duration data.
Conclusions:
- The latent class duration model is more effective in accounting for unobserved heterogeneity in freeway incident clearance times.
- Findings provide data-driven evidence to inform policy and reduce incident clearance durations.
- This research contributes to the body of knowledge on traffic incident management and econometrics.
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