Realistic assessments of school commuting accessibility in areas with infrequent public transport services require accounting for operational delays; however, the impact of these delays has not been sufficiently examined. This study evaluates high-school accessibility in Matsumoto City, a regional city in Japan, using GTFS data representing both scheduled timetables and actual operating conditions. Accessibility levels are assessed under scheduled operations, while the effects of delays are examined through a comparative analysis based on actual delay measurements over a five-day workweek. Furthermore, a sensitivity analysis of travel-time thresholds was conducted. Results show that, when walking, cycling to stations, and public transport use are allowed, 78% of children under 15 can reach at least one high school within a 90-minute round trip, and 67% within a 60-minute round trip. Extending the threshold to 120 minutes enables access to nearly all schools in the city center, but the overall proportion increases only marginally to 81%. Delay impacts are particularly pronounced along bus routes connecting the central station with suburban areas, while in some areas, delays generate idiosyncratic events, where irregular transfers and reduced waiting times result in improved accessibility. Results underscore the need for both short-term measures,such as adjusting school start times, prioritizing buses, and introducing dedicated school routes, and long-term strategies, such as incorporating public transport accessibility into school consolidation decisions, to guarantee fair access to education opportunities without relying on private vehicles.

翻译：针对公共交通服务频率较低地区的通学可达性评估需考虑运营延误的影响，但现有研究对此关注不足。本研究以日本地方城市松本市为案例，利用GTFS数据（涵盖规划时刻表与实际运行状态）评估高中通学可达性。首先基于规划运营条件测算可达性水平，继而通过连续五个工作日的实际延误数据开展对比分析以探究延误效应，并进行了出行时间阈值的敏感性分析。结果表明：在允许步行、骑行至车站及使用公共交通的情况下，78%的15岁以下儿童可在90分钟往返时间内抵达至少一所高中，67%可在60分钟往返时间内完成。当阈值扩展至120分钟时，市中心几乎所有学校均可覆盖，但整体比例仅微增至81%。延误影响在连接中心车站与郊区的公交线路上尤为显著；部分区域因延误产生的特异性事件（如非规则换乘与候车时间缩短）反而提升了可达性。研究结果强调了短期措施（调整学校上课时间、实施公交优先策略、增设通学专线）与长期战略（将公共交通可达性纳入学校布局调整决策）相结合的必要性，以确保不依赖私家车的前提下实现公平的教育机会获取。