Effects of rail transit on individual travel mode shares: A two-dimensional propensity score matching approach

We examine the impact of the opening of the Circle Line (CCL) in Singapore on individuals’ travel mode choice. Using data from cross-sectional surveys conducted before and after the CCL opening, we investigate how individuals’ travel mode choices changed in response to improved accessibility to the rail transit system. The difference-in-differences models show that the CCL opening increased the rail transit mode share and reduced the private car mode share. However, there was no significant impact on the mode share of buses or trip generation. We adopt a two-dimensional propensity score matching approach to adjust for spatial and temporal variations in the treatment and control groups. We find that the effect of the CCL on the promotion of rail usage is stronger in the matched sample model. This study provides new evidence that rail transit investments are effective in encouraging the switch from private cars to rail transit and thus reducing car dependency