Seoul Drew Its Night Bus Routes from Three Billion Phone Records — Epoche B1
Purpose Seoul's night buses, the N routes that run from around midnight until dawn while the subway is shut, were not drawn by planners guessing where people might be. This report sets out how the routes were decided and what the method costs. Method The city worked with a mobile network operator and used around three billion late-night call records, together with data from taxi journeys. Each record shows roughly where a phone was and when. The records were used in groups, as counts of phones in an area rather than as one person's night. Put together, they produce a map of the city between midnight and dawn: not where people live, and not where the day buses go, but where they actually are at three in the morning. Findings Late-night demand is concentrated in a small number of busy corridors, not spread evenly across the city. The routes launched in 2013 were placed along those corridors. The night network is therefore not the day network running later. It is a different shape. Limitations The method has one honest weakness, and it follows directly from its strength. A route drawn to the crowd serves the crowd. A rider in a thin corridor, a cleaner finishing at two or a cook in a quiet district, is still left to the taxi queue. The second limitation is time. The data described a particular year. Neighbourhoods change: one area empties, a new district fills. A map that is never refreshed becomes a picture of a city that no longer exists, and the routes have to be redrawn. Conclusion Evidence can replace guesswork in public transport, but it cannot decide who counts. That question stays with the city. References Seoul Metropolitan Government (2015). Owl Bus: Late-night Bus Routes Designed with Big Data. Seoul Solution, Seoul Metropolitan Government. OECD (2019). Enhancing Access to and Sharing of Data. OECD Publishing.