RT Journal Article SR Electronic T1 Smart Device Recreation Data JF Land Economics JO Land Econ FD University of Wisconsin Press SP 011626-0005 DO 10.3368/le.102.3.011626-0005 A1 Duff, Cameron A1 Giguere, Chris A1 Murray, Jason YR 2026 UL http://le.uwpress.org/content/early/2026/03/05/le.102.3.011626-0005.abstract AB Human mobility data (MD) from smartphones may offer a scalable alternative to fieldwork for Natural Resource Damage Assessments (NRDAs) and non-market valuation. We test MD's utility for estimating recreational demand changes after a 2019 Houston tank fire. We apply count regressions and zonal travel cost models to calculate welfare losses. While this MD dataset reflects expected temporal patterns, comparisons with reference data reveal that "coverage rates" vary significantly across sites. This measurement error complicates counterfactual predictions. Economists should use caution when deriving absolute recreational value from MD.