Data and code for: Nighttime signaling beyond population and built-environment baselines: Spatial evidence and interpretive boundaries from Beijing

Hidden nighttime presence (HNP) measures whether nighttime mobile-signaling volume in a built-up block persistently exceeds the expectation set by conventional population (WorldPop) and aboveground built volume (CNBH), across two social-calendar contexts (national holiday vs regular workday, October 2023). The study domain is 31,135 built-up blocks in Beijing (3×3 cells of a 250 m lattice); 18,319 blocks (58.8%) carry a valid two-date-positive HNP score, of which 1,833 form the nominal upper decile (5.9% of all built-up blocks). HNP is validated against geocoded records of underground illegal residential occupancy (Group A), non-underground concentrated overnight accommodation (Group B), an official negative-control list (Group D), matched background blocks (Group C), and three independent administrative record sets (2014 municipal remediation list, 2019 planning permits, 2024–2026 penalty notices).