Nonlinear and Interaction Effects of the Built Environment on Bus Travel Behavior among People with Disabilities: Evidence from Wuhan, China

People with disabilities (PWDs) may exhibit distinctive spatiotemporal patterns of bus travel because of their specific physical conditions and travel preferences, which may in turn lead to different associations with the built environment compared with people without disabilities. However, these differences have received limited scholarly attention. This study addresses this gap by comparing the bus travel behaviors of people with and without disabilities in Wuhan, China. The results show that PWDs have significantly higher bus travel frequencies than people without disabilities on both weekdays (3.58 vs. 2.86 trips) and weekends (3.32 vs. 2.63 trips). In terms of spatial distribution, bus trips made by PWDs are more concentrated in central urban areas, whereas those made by people without disabilities are more clustered around transport hubs and employment centers. Further analysis using XGBoost and SHAP reveals significant heterogeneity in the effects of the built environment on bus ridership between the two groups. For PWDs, the three most important factors influencing bus ridership on weekday are road density (14.71