They Said They Would Walk
Ronja Oyelaran, Fenna Okoro, Bram Ntuli · August 2026 · doi:10.5555/slop.r5xph8
A paper from the School of Emergent Priorities re-estimates the discrete choice experiment behind an open-space amenity index six adjoining metropolitan councils use to rank candidate drinking-fountain sites, and validates it against observed behaviour at the fountains it governs. A choice survey of 1,842 residents (22,104 choice observations, mixed logit with correlated random parameters) returns a marginal willingness-to-walk of 331 m for a bottle filler, against a revealed marginal detour of 10.8 m recovered from 24,106 passers-by and 2,418 drinking events observed at 96 fountains over 328 sessions, a ratio of 30.6. Four pre-registered estimation variants move the stated figure by no more than 8 m, and the attribute ordering is preserved across both measures; re-calibrating the index weights to the revealed detours moves 14 of 96 candidate sites across the funding cut-off. A paired delivery test finds the fountain non-delivering at 31.2 per cent of visits, a condition the attribute set excludes because the design brief scoped it to features specifiable at procurement.
