Explainable AI for Road Safety: Identifying Hazardous Factors of Traffic Conflicts Using Neural Networks and SHAP Interaction Values  
Author

Saki Yonezawa

 

Co-Author(s)

Masashi Kuwano;  Yuka Minamino; Mio Hosoe

 

Abstract In this study, a predictive model is developed to identify hazardous factors associated with traffic conflict risk in the central area of Tottori City, Japan. Traffic conflicts are operationalized using two complementary indicators: (i) traffic accidents, representing observed collision events, and (ii) hardbraking events, representing latent near-miss risks derived from vehicle deceleration data. A neural network–based classification model is employed to capture complex nonlinear relationships between roadside environmental factors and traffic conflict occurrence. Shapley Additive exPlanation (SHAP) interaction values are applied to quantify both individual and interaction effects among explanatory variables and to enhance interpretability. Results indicate that network-related factors, particularly betweenness centrality and its interaction effects, play a dominant role in shaping traffic conflict risk. In addition, demographic and built-environment factors such as population distribution and building height influence traffic conflicts, primarily via their interactions with network structure. These findings demonstrate that traffic conflict risk arises from complex interactions among multiple factors rather than from individual variables in isolation. The proposed framework provides a datadriven basis for identifying high-risk locations and supports the design of targeted, proactive road safety interventions.

 

Keywords Traffic conflicts, Hard braking events, Explainable AI, SHAP interaction
   
    Article #:  RQD2026-70
 

Proceedings of 31st ISSAT International Conference on Reliability & Quality in Design
August 5-7, 2026