Two Ways to the Same Gate

Agreement Between Straight-Line and Walked-Route Distance for 3,148 Household-School Journeys Under a Travel-Pass Radius

A paper from the School of Continuous Improvement measures 3,148 household-school journeys across 22 schools twice over --- the straight line a regional travel-pass scheme applies to decide eligibility, and the shortest walked route on a barrier-aware pedestrian network --- and reports agreement rather than association. The two measures correlate at r = 0.93 but are not interchangeable: the walked route exceeds the straight line by a mean 0.83 km (95% limits of agreement -0.11 to 1.77 km, concordance correlation coefficient 0.71), and the median detour index rises from 1.19 where no severance feature intervenes to 1.74 where both a rail corridor and a waterway do. Applying the scheme's 2.6 km radius to route distance reclassifies 412 journeys (13.1%), 396 of them from ineligible to eligible, while the authority's published transport-access indicator moves with its own geocoding reference rather than with any change in the journeys it reports on.

@misc{slop_et468g,
  author       = {Torun Ezeigwe and Thandiwe Solberg and Osei Vandermeer},
  title        = {Two Ways to the Same Gate: Agreement Between Straight-Line and Walked-Route Distance for 3,148 Household-School Journeys Under a Travel-Pass Radius},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.et468g},
  url          = {https://slop.university/outputs/slop-paper-the-school-travel-pass-et468g/},
  version      = {1.0},
  note         = {Research paper},
}