Distance deterrence in Seoul mobility varies across space, time and age groups

How strongly does distance discourage travel within a city? A new study of the Seoul Metropolitan Area suggests the answer depends heavily on where you are, when you travel, and how old you are, with transit accessibility emerging as a key factor linked to weaker distance deterrence.

Distance deterrence, often quantified through the gravity model, has long been used to characterize urban mobility. Yet which urban and contextual features are associated with its variation within a single city has remained unclear. The research, published in EPJ Data Science, addresses this question using large-scale origin–destination mobility data comprising about 4.8 billion trips across the Seoul Metropolitan Area.

The team estimated town-level distance exponents with a gravity model, a measure of how strongly travel between two places falls off with the distance separating them. They then examined how these exponents vary in space and time using XGBoost, a machine learning method, interpreted with SHapley Additive exPlanations (SHAP), a technique that reveals how individual features contribute to a model’s predictions.

The analysis shows that distance deterrence follows a core–periphery pattern. Deterrence generally strengthens from the urban core toward the periphery, meaning that trips in outlying areas are more strongly constrained by distance than trips in central districts.

However, the pattern is not uniform. Localized areas of weak deterrence appear near major metro stations, suggesting that proximity to rapid transit allows residents to make longer trips with less penalty from distance than would otherwise be expected.

The spatial pattern is accompanied by temporal variation. Distance deterrence generally increases from morning to afternoon and decreases during day-off periods, indicating that the friction of distance is not a fixed property of a city but shifts with daily and weekly rhythms of activity.

Notably, the day-off pattern reverses among working-age groups in transit-rich urban cores.

Overall, transit accessibility emerges as a key factor associated with lower distance deterrence, with associations that vary across time and population groups. The findings suggest that distance deterrence reflects nonlinear and complex relationships with urban structure, transit accessibility, and sociotemporal factors, making it a spatiotemporally sensitive indicator of accessibility disparities across urban space.

The study is based on a single metropolitan area, and the authors describe the relationships as associations rather than causal effects. Even so, the work offers a data-driven template for how massive mobility datasets can expose the uneven geography of accessibility within cities.

Subject of Research: Spatial and temporal variation of distance deterrence in urban mobility across the Seoul Metropolitan Area

Article Title: Explaining distance deterrence variation in urban mobility with spatiotemporal features

Article References: Kang, S., & Hong, I. (2026). Explaining distance deterrence variation in urban mobility with spatiotemporal features. EPJ Data Science. https://doi.org/10.1140/epjds/s13688-026-00702-w

Image Credits: AI Generated

DOI: 10.1140/epjds/s13688-026-00702-w

Keywords: urban mobility, distance deterrence, gravity model, Seoul Metropolitan Area, transit accessibility, XGBoost, SHAP, accessibility disparities, origin-destination data, core-periphery, commuting, public transit