We investigate the impact of the Circle Line (CL) opening in Singapore on individuals’ vehicle kilometers traveled (VKT) using the two repeated cross-sectional travel surveys. In the unmatched difference-in-differences analyses, the CL opening reduces the average VKT by individuals living in the 500-meter buffer zone (treatment) by 38.3% relative to those residing in the 500-1500-meter buffer zone (control) of CL stations. We apply a two-dimensional propensity-score-matching approach to control the spatial heterogeneity of individuals in the treatment and control zones and the temporal heterogeneity of individuals in the pre-CL and after-CL periods due to residential relocation. The CL effect increases to 48.0% with the matched samples. We apply a two-stage regression to test the impact of the CL opening on VKT in the extensive and intensive margins. We find that the CL only affects individuals’ driving decisions but does not significantly affect driving distance. The study has significant policy implications for rail transit investment decisions and sustainable urban transport.

我们使用两个重复的横断面旅行调查调查新加坡环线 (CL) 开通对个人车辆行驶公里数 (VKT) 的影响。在无与伦比的差异差异分析中，相对于居住在 500-1500 米缓冲区（控制）的个人，CL 开放将生活在 500 米缓冲区（处理）的个人的平均 VKT 降低了 38.3% CL站。我们应用二维倾向得分匹配方法来控制处理区和控制区中个体的空间异质性以及由于居住搬迁导致的 CL 前和 CL 后个体的时间异质性。匹配样品的 CL 效应增加到 48.0%。我们应用两阶段回归来测试 CL 开放对广泛和密集利润率中 VKT 的影响。我们发现 CL 仅影响个人的驾驶决策，但不会显着影响驾驶距离。该研究对轨道交通投资决策和可持续城市交通具有重要的政策意义。